diff --git a/VERSION.txt b/VERSION.txt
index f4b80628c60..921beff9a72 100644
--- a/VERSION.txt
+++ b/VERSION.txt
@@ -16,4 +16,4 @@
 // @license       https://opensource.org/licenses/mit-license.php MIT License
 // +--------------------------------------------------------------------------------------------+ //
 ////////////////////////////////////////////////////////////////////////////////////////////////////
-5.3.3
+5.4.0-dev
diff --git a/composer.json b/composer.json
index ca5583e4b73..19a8720360e 100644
--- a/composer.json
+++ b/composer.json
@@ -37,6 +37,7 @@
         "psr/http-message": "^1.1 || ^2.0",
         "psr/http-server-handler": "^1.0.2",
         "psr/http-server-middleware": "^1.0.2",
+        "psr/link": "^2.0",
         "psr/log": "^3.0",
         "psr/simple-cache": "^2.0 || ^3.0"
     },
@@ -44,6 +45,7 @@
         "cakephp/cache": "self.version",
         "cakephp/collection": "self.version",
         "cakephp/console": "self.version",
+        "cakephp/container": "self.version",
         "cakephp/core": "self.version",
         "cakephp/database": "self.version",
         "cakephp/datasource": "self.version",
@@ -75,6 +77,7 @@
         "psr/http-factory-implementation": "^1.0",
         "psr/http-server-handler-implementation": "^1.0",
         "psr/http-server-middleware-implementation": "^1.0",
+        "psr/link-implementation": "^2.0",
         "psr/log-implementation": "^3.0",
         "psr/simple-cache-implementation": "^3.0"
     },
@@ -115,7 +118,10 @@
             "Named\\": "tests/test_app/Plugin/Named/src/",
             "TestTheme\\": "tests/test_app/Plugin/TestTheme/src/",
             "PluginJs\\": "tests/test_app/Plugin/PluginJs/src/"
-        }
+        },
+        "files": [
+            "tests/TestCase/Container/Asset/function.php"
+        ]
     },
     "scripts": {
         "check": [
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index f1cd44d7092..1e227e7d093 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -51,7 +51,7 @@ parameters:
 		-
 			message: '#^Unsafe usage of new static\(\)\.$#'
 			identifier: new.static
-			count: 8
+			count: 9
 			path: src/Database/Expression/QueryExpression.php
 
 		-
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index c8e0d5af07a..0c9ada3f739 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -19,6 +19,7 @@ parameters:
 		- identifier: method.internalClass
 		- identifier: new.internalClass
 		- identifier: trait.unused
+		- identifier: method.templateTypeNotInParameter
 		-
 			identifier: generics.interfaceConflict
 			paths:
diff --git a/src/Cache/composer.json b/src/Cache/composer.json
index e0b42708510..d5c50625d15 100644
--- a/src/Cache/composer.json
+++ b/src/Cache/composer.json
@@ -23,8 +23,8 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
-        "cakephp/event": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
+        "cakephp/event": "5.4.*@dev",
         "psr/simple-cache": "^2.0 || ^3.0"
     },
     "provide": {
diff --git a/src/Collection/CollectionInterface.php b/src/Collection/CollectionInterface.php
index e28527760e0..1575d8c61c9 100644
--- a/src/Collection/CollectionInterface.php
+++ b/src/Collection/CollectionInterface.php
@@ -26,6 +26,11 @@
  * list of elements exposing a number of traversing and extracting method for
  * generating other collections.
  *
+ * @method \Cake\Collection\CollectionInterface<int, TValue> keys() Returns a new collection containing only the keys of the elements.
+ * @method \Cake\Collection\CollectionInterface<int, TValue> values() Returns a new collection containing only the values, re-indexed with consecutive integers.
+ * @method string implode(string $glue, callable|string|null $path = null) Concatenates all elements into a string using the provided glue.
+ * @method \Cake\Collection\CollectionInterface<TKey, TValue> when(mixed $condition, callable $callback) Applies callback if condition is truthy.
+ * @method \Cake\Collection\CollectionInterface<TKey, TValue> unless(mixed $condition, callable $callback) Applies callback if condition is falsy.
  * @template TKey
  * @template-covariant TValue
  * @template-extends \Iterator<TKey, TValue>
diff --git a/src/Collection/CollectionTrait.php b/src/Collection/CollectionTrait.php
index 6712b3954a8..e150d23f6d3 100644
--- a/src/Collection/CollectionTrait.php
+++ b/src/Collection/CollectionTrait.php
@@ -1224,6 +1224,79 @@ public function countKeys(): int
         return count($this->toArray());
     }
 
+    /**
+     * Returns a new collection containing only the keys of the elements.
+     *
+     * @return \Cake\Collection\CollectionInterface<int, TValue>
+     */
+    public function keys(): CollectionInterface
+    {
+        $generator = function (): Generator {
+            foreach ($this->optimizeUnwrap() as $key => $value) {
+                yield $key;
+            }
+        };
+
+        return $this->newCollection($generator());
+    }
+
+    /**
+     * Returns a new collection containing only the values, re-indexed with consecutive integers.
+     *
+     * @return \Cake\Collection\CollectionInterface<int, TValue>
+     */
+    public function values(): CollectionInterface
+    {
+        $generator = function (): Generator {
+            foreach ($this->optimizeUnwrap() as $value) {
+                yield $value;
+            }
+        };
+
+        return $this->newCollection($generator());
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function implode(string $glue, callable|string|null $path = null): string
+    {
+        $items = $this;
+        if ($path !== null) {
+            $items = $items->extract($path);
+        }
+
+        return implode($glue, $items->toList());
+    }
+
+    /**
+     * Applies callback if condition is truthy.
+     *
+     * @return \Cake\Collection\CollectionInterface<TKey, TValue>
+     */
+    public function when(mixed $condition, callable $callback): CollectionInterface
+    {
+        if ($condition) {
+            return $callback($this, $condition);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Applies callback if condition is falsy.
+     *
+     * @return \Cake\Collection\CollectionInterface<TKey, TValue>
+     */
+    public function unless(mixed $condition, callable $callback): CollectionInterface
+    {
+        if (!$condition) {
+            return $callback($this, $condition);
+        }
+
+        return $this;
+    }
+
     /**
      * Unwraps this iterator and returns the simplest
      * traversable that can be used for getting the data out
diff --git a/src/Command/Helper/BannerHelper.php b/src/Command/Helper/BannerHelper.php
index 840f4464367..bea6ae43f8b 100644
--- a/src/Command/Helper/BannerHelper.php
+++ b/src/Command/Helper/BannerHelper.php
@@ -1,107 +1,9 @@
 <?php
 declare(strict_types=1);
 
-/**
- * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
- * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- *
- * Licensed under The MIT License
- * For full copyright and license information, please see the LICENSE.txt
- * Redistributions of files must retain the above copyright notice.
- *
- * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- * @link          https://cakephp.org CakePHP Project
- * @since         5.1.0
- * @license       https://opensource.org/licenses/mit-license.php MIT License
- */
-namespace Cake\Command\Helper;
+use Cake\Console\Helper\BannerHelper;
+use function Cake\Core\deprecationWarning;
 
-use Cake\Console\Helper;
-use InvalidArgumentException;
+deprecationWarning('5.4.0', 'Cake\Command\Helper\BannerHelper is deprecated. Use Cake\Console\Helper\BannerHelper instead.');
 
-/**
- * Banner command helper.
- *
- * Formats one or more lines of text into a large banner with
- * padding and a blank line below.
- */
-class BannerHelper extends Helper
-{
-    /**
-     * @var int The horizontal padding that is added to the longest line.
-     */
-    private int $padding = 2;
-
-    /**
-     * @var string The console output style to use on the banner.
-     */
-    private string $style = 'success.bg';
-
-    /**
-     * Modify the padding of the helper
-     *
-     * @param int $padding The padding value to use.
-     * @return $this
-     */
-    public function withPadding(int $padding)
-    {
-        if ($padding < 0) {
-            throw new InvalidArgumentException('padding must be greater than 0');
-        }
-        $this->padding = $padding;
-
-        return $this;
-    }
-
-    /**
-     * Modify the padding of the helper
-     *
-     * @param string $style The style value to use.
-     * @return $this
-     */
-    public function withStyle(string $style)
-    {
-        $this->style = $style;
-
-        return $this;
-    }
-
-    /**
-     * Output a banner
-     *
-     * @param array $args The messages to output
-     * @return void
-     */
-    public function output(array $args): void
-    {
-        if ($args === []) {
-            throw new InvalidArgumentException('At least one argument is required');
-        }
-
-        $lengths = array_map(mb_strlen(...), $args);
-        $maxLength = max($lengths);
-        $bannerLength = $maxLength + $this->padding * 2;
-        $start = "<{$this->style}>";
-        $end = "</{$this->style}>";
-
-        $lines = [
-            '',
-            $start . str_repeat(' ', $bannerLength) . $end,
-        ];
-        foreach ($args as $line) {
-            $lineLength = mb_strlen($line);
-            $linePadding = (int)max($this->padding, $bannerLength - $lineLength - $this->padding);
-
-            $lines[] = $start .
-                str_repeat(' ', $this->padding) .
-                $line .
-                str_repeat(' ', $linePadding) .
-                $end;
-        }
-
-        $lines[] = $start . str_repeat(' ', $bannerLength) . $end;
-        $lines[] = '';
-
-        $this->_io->out($lines);
-    }
-}
+class_exists(BannerHelper::class);
diff --git a/src/Command/Helper/ProgressHelper.php b/src/Command/Helper/ProgressHelper.php
index f14d54c31ca..63689a88111 100644
--- a/src/Command/Helper/ProgressHelper.php
+++ b/src/Command/Helper/ProgressHelper.php
@@ -1,163 +1,9 @@
 <?php
 declare(strict_types=1);
 
-/**
- * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
- * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- *
- * Licensed under The MIT License
- * For full copyright and license information, please see the LICENSE.txt
- * Redistributions of files must retain the above copyright notice.
- *
- * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- * @link          https://cakephp.org CakePHP Project
- * @since         3.1.0
- * @license       https://opensource.org/licenses/mit-license.php MIT License
- */
-namespace Cake\Command\Helper;
+use Cake\Console\Helper\ProgressHelper;
+use function Cake\Core\deprecationWarning;
 
-use Cake\Console\Helper;
-use InvalidArgumentException;
+deprecationWarning('5.4.0', 'Cake\Command\Helper\ProgressHelper is deprecated. Use Cake\Console\Helper\ProgressHelper instead.');
 
-/**
- * Create a progress bar using a supplied callback.
- *
- * ## Usage
- *
- * The ProgressHelper can be accessed from shells using the helper() method
- *
- * ```
- * $this->helper('Progress')->output(['callback' => function ($progress) {
- *     // Do work
- *     $progress->increment();
- * }]);
- * ```
- */
-class ProgressHelper extends Helper
-{
-    /**
-     * Default value for progress bar total value.
-     * Percent completion is derived from progress/total
-     */
-    protected const DEFAULT_TOTAL = 100;
-
-    /**
-     * Default value for progress bar width
-     */
-    protected const DEFAULT_WIDTH = 80;
-
-    /**
-     * The current progress.
-     *
-     * @var float|int
-     */
-    protected float|int $_progress = 0;
-
-    /**
-     * The total number of 'items' to progress through.
-     *
-     * @var int
-     */
-    protected int $_total = self::DEFAULT_TOTAL;
-
-    /**
-     * The width of the bar.
-     *
-     * @var int
-     */
-    protected int $_width = self::DEFAULT_WIDTH;
-
-    /**
-     * Output a progress bar.
-     *
-     * Takes a number of options to customize the behavior:
-     *
-     * - `total` The total number of items in the progress bar. Defaults
-     *   to 100.
-     * - `width` The width of the progress bar. Defaults to 80.
-     * - `callback` The callback that will be called in a loop to advance the progress bar.
-     *
-     * @param array $args The arguments/options to use when outputting the progress bar.
-     * @return void
-     */
-    public function output(array $args): void
-    {
-        $args += ['callback' => null];
-        if (isset($args[0])) {
-            $args['callback'] = $args[0];
-        }
-        if (!$args['callback'] || !is_callable($args['callback'])) {
-            throw new InvalidArgumentException('Callback option must be a callable.');
-        }
-        $this->init($args);
-
-        $callback = $args['callback'];
-
-        $this->_io->out('', 0);
-        while ($this->_progress < $this->_total) {
-            $callback($this);
-            $this->draw();
-        }
-        $this->_io->out('');
-    }
-
-    /**
-     * Initialize the progress bar for use.
-     *
-     * - `total` The total number of items in the progress bar. Defaults
-     *   to 100.
-     * - `width` The width of the progress bar. Defaults to 80.
-     *
-     * @param array<string, mixed> $args The initialization data.
-     * @return $this
-     */
-    public function init(array $args = [])
-    {
-        $args += ['total' => self::DEFAULT_TOTAL, 'width' => self::DEFAULT_WIDTH];
-        $this->_progress = 0;
-        $this->_width = $args['width'];
-        $this->_total = $args['total'];
-
-        return $this;
-    }
-
-    /**
-     * Increment the progress bar.
-     *
-     * @param float|int $num The amount of progress to advance by.
-     * @return $this
-     */
-    public function increment(float|int $num = 1)
-    {
-        $this->_progress = min(max(0, $this->_progress + $num), $this->_total);
-
-        return $this;
-    }
-
-    /**
-     * Render the progress bar based on the current state.
-     *
-     * @return $this
-     */
-    public function draw()
-    {
-        $numberLen = strlen(' 100%');
-        $complete = round($this->_progress / $this->_total, 2);
-        $barLen = ($this->_width - $numberLen) * $this->_progress / $this->_total;
-        $bar = '';
-        if ($barLen > 1) {
-            $bar = str_repeat('=', (int)$barLen - 1) . '>';
-        }
-
-        $pad = ceil($this->_width - $numberLen - $barLen);
-        if ($pad > 0) {
-            $bar .= str_repeat(' ', (int)$pad);
-        }
-        $percent = ($complete * 100) . '%';
-        $bar .= str_pad($percent, $numberLen, ' ', STR_PAD_LEFT);
-
-        $this->_io->overwrite($bar, 0);
-
-        return $this;
-    }
-}
+class_exists(ProgressHelper::class);
diff --git a/src/Command/Helper/TableHelper.php b/src/Command/Helper/TableHelper.php
index 741fa43fa7d..683cc6fc126 100644
--- a/src/Command/Helper/TableHelper.php
+++ b/src/Command/Helper/TableHelper.php
@@ -1,185 +1,9 @@
 <?php
 declare(strict_types=1);
 
-/**
- * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
- * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- *
- * Licensed under The MIT License
- * For full copyright and license information, please see the LICENSE.txt
- * Redistributions of files must retain the above copyright notice.
- *
- * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- * @since         3.1.0
- * @license       https://opensource.org/licenses/mit-license.php MIT License
- */
-namespace Cake\Command\Helper;
+use Cake\Console\Helper\TableHelper;
+use function Cake\Core\deprecationWarning;
 
-use Cake\Console\Helper;
-use UnexpectedValueException;
+deprecationWarning('5.4.0', 'Cake\Command\Helper\TableHelper is deprecated. Use Cake\Console\Helper\TableHelper instead.');
 
-/**
- * Create a visually pleasing ASCII art table
- * from 2-dimensional array data.
- */
-class TableHelper extends Helper
-{
-    /**
-     * Default config for this helper.
-     *
-     * @var array<string, mixed>
-     */
-    protected array $_defaultConfig = [
-        'headers' => true,
-        'rowSeparator' => false,
-        'headerStyle' => 'info',
-    ];
-
-    /**
-     * Calculate the column widths
-     *
-     * @param array $rows The rows on which the column's width will be calculated on.
-     * @return array<int>
-     */
-    protected function _calculateWidths(array $rows): array
-    {
-        $widths = [];
-        foreach ($rows as $line) {
-            foreach (array_values($line) as $k => $v) {
-                $columnLength = $this->_cellWidth((string)$v);
-                if ($columnLength >= ($widths[$k] ?? 0)) {
-                    $widths[$k] = $columnLength;
-                }
-            }
-        }
-
-        return $widths;
-    }
-
-    /**
-     * Get the width of a cell exclusive of style tags.
-     *
-     * @param string $text The text to calculate a width for.
-     * @return int The width of the textual content in visible characters.
-     */
-    protected function _cellWidth(string $text): int
-    {
-        if ($text === '') {
-            return 0;
-        }
-
-        if (!str_contains($text, '<') && !str_contains($text, '>')) {
-            return mb_strwidth($text);
-        }
-
-        $styles = $this->_io->styles();
-        $tags = implode('|', array_keys($styles));
-        $text = (string)preg_replace('#</?(?:' . $tags . ')>#', '', $text);
-
-        return mb_strwidth($text);
-    }
-
-    /**
-     * Output a row separator.
-     *
-     * @param array<int> $widths The widths of each column to output.
-     * @return void
-     */
-    protected function _rowSeparator(array $widths): void
-    {
-        $out = '';
-        foreach ($widths as $column) {
-            $out .= '+' . str_repeat('-', $column + 2);
-        }
-        $out .= '+';
-        $this->_io->out($out);
-    }
-
-    /**
-     * Output a row.
-     *
-     * @param array $row The row to output.
-     * @param array<int> $widths The widths of each column to output.
-     * @param array<string, mixed> $options Options to be passed.
-     * @return void
-     */
-    protected function _render(array $row, array $widths, array $options = []): void
-    {
-        if ($row === []) {
-            return;
-        }
-
-        $out = '';
-        foreach (array_values($row) as $i => $column) {
-            $column = (string)$column;
-            $pad = $widths[$i] - $this->_cellWidth($column);
-            if (!empty($options['style'])) {
-                $column = $this->_addStyle($column, $options['style']);
-            }
-            if ($column !== '' && preg_match('#(.*)<text-right>.+</text-right>(.*)#', $column, $matches)) {
-                if ($matches[1] !== '' || $matches[2] !== '') {
-                    throw new UnexpectedValueException('You cannot include text before or after the text-right tag.');
-                }
-                $column = str_replace(['<text-right>', '</text-right>'], '', $column);
-                $out .= '| ' . str_repeat(' ', $pad) . $column . ' ';
-            } else {
-                $out .= '| ' . $column . str_repeat(' ', $pad) . ' ';
-            }
-        }
-        $out .= '|';
-        $this->_io->out($out);
-    }
-
-    /**
-     * Output a table.
-     *
-     * Data will be output based on the order of the values
-     * in the array. The keys will not be used to align data.
-     *
-     * @param array $args The data to render out.
-     * @return void
-     */
-    public function output(array $args): void
-    {
-        if (!$args) {
-            return;
-        }
-
-        $this->_io->setStyle('text-right', ['text' => null]);
-
-        $config = $this->getConfig();
-        $widths = $this->_calculateWidths($args);
-
-        $this->_rowSeparator($widths);
-        if ($config['headers'] === true) {
-            $this->_render(array_shift($args), $widths, ['style' => $config['headerStyle']]);
-            $this->_rowSeparator($widths);
-        }
-
-        if (!$args) {
-            return;
-        }
-
-        foreach ($args as $line) {
-            $this->_render($line, $widths);
-            if ($config['rowSeparator'] === true) {
-                $this->_rowSeparator($widths);
-            }
-        }
-        if ($config['rowSeparator'] !== true) {
-            $this->_rowSeparator($widths);
-        }
-    }
-
-    /**
-     * Add style tags
-     *
-     * @param string $text The text to be surrounded
-     * @param string $style The style to be applied
-     * @return string
-     */
-    protected function _addStyle(string $text, string $style): string
-    {
-        return '<' . $style . '>' . $text . '</' . $style . '>';
-    }
-}
+class_exists(TableHelper::class);
diff --git a/src/Command/Helper/TreeHelper.php b/src/Command/Helper/TreeHelper.php
index 5820e4be014..fea9220376e 100644
--- a/src/Command/Helper/TreeHelper.php
+++ b/src/Command/Helper/TreeHelper.php
@@ -1,124 +1,9 @@
 <?php
 declare(strict_types=1);
 
-/**
- * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
- * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- *
- * Licensed under The MIT License
- * For full copyright and license information, please see the LICENSE.txt
- * Redistributions of files must retain the above copyright notice.
- *
- * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
- * @link          https://cakephp.org CakePHP Project
- * @since         5.3.0
- * @license       https://opensource.org/licenses/mit-license.php MIT License
- */
-namespace Cake\Command\Helper;
+use Cake\Console\Helper\TreeHelper;
+use function Cake\Core\deprecationWarning;
 
-use BackedEnum;
-use Cake\Console\Helper;
-use Cake\Database\Type\EnumLabelInterface;
-use Closure;
-use UnitEnum;
+deprecationWarning('5.4.0', 'Cake\Command\Helper\TreeHelper is deprecated. Use Cake\Console\Helper\TreeHelper instead.');
 
-/**
- * Tree command helper.
- *
- * Formats nested arrays into a tree with dashes and pipes.
- */
-class TreeHelper extends Helper
-{
-    /**
-     * @inheritDoc
-     */
-    protected array $_defaultConfig = [
-        'baseIndent' => 0,
-        'elementIndent' => 0,
-    ];
-
-    /**
-     * Outputs an array in tree form.
-     *
-     * @param array $args Tree array
-     * @return void
-     */
-    public function output(array $args): void
-    {
-        $prefix = str_repeat(' ', $this->_config['baseIndent']);
-        $this->outputArray($args, $prefix, topLevel: true);
-    }
-
-    /**
-     * Output an array in a tree.
-     *
-     * @param array $array
-     * @param string $prefix
-     * @param bool $topLevel
-     * @return void
-     */
-    protected function outputArray(array $array, string $prefix, bool $topLevel): void
-    {
-        $i = 1;
-        $numValues = count($array);
-        $elementPrefix = $topLevel ? '' : str_repeat(' ', $this->_config['elementIndent']);
-        foreach ($array as $key => $value) {
-            $isLast = $i++ === $numValues;
-            $marker = $isLast ? '└── ' : '├── ';
-            $indent = $isLast ? '    ' : '│   ';
-            $this->outputElement($key, $value, $prefix . $elementPrefix, $marker, $indent);
-        }
-    }
-
-    /**
-     * Output an array element.
-     *
-     * @param string|int $key
-     * @param mixed $value
-     * @param string $prefix
-     * @param string $marker
-     * @param string $indent
-     * @return void
-     */
-    protected function outputElement(
-        string|int $key,
-        mixed $value,
-        string $prefix,
-        string $marker,
-        string $indent,
-    ): void {
-        if (is_array($value)) {
-            $this->_io->out($prefix . $marker . $key);
-            $this->outputArray($value, $prefix . $indent, topLevel: false);
-        } elseif (is_string($key)) {
-            $this->_io->out($prefix . $marker . $key);
-            $this->outputValue($value, $prefix . $indent . '└── ');
-        } else {
-            $this->outputValue($value, $prefix . $marker);
-        }
-    }
-
-    /**
-     * Output a value in a tree.
-     *
-     * @param mixed $value
-     * @param string $prefix
-     * @return void
-     */
-    protected function outputValue(mixed $value, string $prefix): void
-    {
-        if ($value instanceof Closure) {
-            $this->_io->out($prefix . $value());
-        } elseif ($value instanceof EnumLabelInterface) {
-            $this->_io->out($prefix . $value->label());
-        } elseif ($value instanceof BackedEnum) {
-            $this->_io->out($prefix . $value->value);
-        } elseif ($value instanceof UnitEnum) {
-            $this->_io->out($prefix . $value->name);
-        } elseif (is_bool($value)) {
-            $this->_io->out($prefix . ($value ? 'true' : 'false'));
-        } else {
-            $this->_io->out($prefix . $value);
-        }
-    }
-}
+class_exists(TreeHelper::class);
diff --git a/src/Command/I18nExtractCommand.php b/src/Command/I18nExtractCommand.php
index 31a66abd952..6dd75851b9c 100644
--- a/src/Command/I18nExtractCommand.php
+++ b/src/Command/I18nExtractCommand.php
@@ -16,15 +16,16 @@
  */
 namespace Cake\Command;
 
-use Cake\Command\Helper\ProgressHelper;
 use Cake\Console\Arguments;
 use Cake\Console\ConsoleIo;
 use Cake\Console\ConsoleOptionParser;
+use Cake\Console\Helper\ProgressHelper;
 use Cake\Core\App;
 use Cake\Core\Configure;
 use Cake\Core\Exception\CakeException;
 use Cake\Core\Plugin;
 use Cake\Utility\Filesystem;
+use Cake\Utility\Fs\Finder;
 use Cake\Utility\Inflector;
 
 /**
@@ -847,15 +848,19 @@ protected function _searchFiles(): void
                 continue;
             }
             $path .= DIRECTORY_SEPARATOR;
-            $fs = new Filesystem();
-            $files = $fs->findRecursive($path, '/\.php$/');
-            $files = array_keys(iterator_to_array($files));
-            sort($files);
-            if ($pattern) {
-                $files = preg_grep($pattern, $files, PREG_GREP_INVERT) ?: [];
-                $files = array_values($files);
+            $files = (new Finder())
+                ->in($path)
+                ->name('*.php')
+                ->files();
+            foreach ($files as $file) {
+                $this->_files[] = $file->getPathname();
             }
-            $this->_files = array_merge($this->_files, $files);
+        }
+        $this->_files = array_unique($this->_files);
+        sort($this->_files);
+        if ($pattern) {
+            $this->_files = preg_grep($pattern, $this->_files, PREG_GREP_INVERT) ?: [];
+            $this->_files = array_values($this->_files);
         }
         $this->_files = array_unique($this->_files);
     }
diff --git a/src/Command/PluginAssetsCopyCommand.php b/src/Command/PluginAssetsCopyCommand.php
index 2221e374e17..c418c80fd46 100644
--- a/src/Command/PluginAssetsCopyCommand.php
+++ b/src/Command/PluginAssetsCopyCommand.php
@@ -55,9 +55,6 @@ public static function getDescription(): string
      */
     public function execute(Arguments $args, ConsoleIo $io): ?int
     {
-        $this->io = $io;
-        $this->args = $args;
-
         $name = $args->getArgument('name');
         $overwrite = (bool)$args->getOption('overwrite');
         $this->_process($this->_list($name), true, $overwrite);
diff --git a/src/Command/PluginAssetsRemoveCommand.php b/src/Command/PluginAssetsRemoveCommand.php
index b0d613b2e27..335757b0921 100644
--- a/src/Command/PluginAssetsRemoveCommand.php
+++ b/src/Command/PluginAssetsRemoveCommand.php
@@ -54,9 +54,6 @@ public static function getDescription(): string
      */
     public function execute(Arguments $args, ConsoleIo $io): ?int
     {
-        $this->io = $io;
-        $this->args = $args;
-
         $name = $args->getArgument('name');
         $plugins = $this->_list($name);
 
diff --git a/src/Command/PluginAssetsSymlinkCommand.php b/src/Command/PluginAssetsSymlinkCommand.php
index cf2ed4bc91f..f4714a79fac 100644
--- a/src/Command/PluginAssetsSymlinkCommand.php
+++ b/src/Command/PluginAssetsSymlinkCommand.php
@@ -56,9 +56,6 @@ public static function getDescription(): string
      */
     public function execute(Arguments $args, ConsoleIo $io): ?int
     {
-        $this->io = $io;
-        $this->args = $args;
-
         $name = $args->getArgument('name');
         $overwrite = (bool)$args->getOption('overwrite');
         $relative = (bool)$args->getOption('relative');
diff --git a/src/Command/PluginAssetsTrait.php b/src/Command/PluginAssetsTrait.php
index 267a7acefa9..d9d4574ec4b 100644
--- a/src/Command/PluginAssetsTrait.php
+++ b/src/Command/PluginAssetsTrait.php
@@ -16,8 +16,6 @@
  */
 namespace Cake\Command;
 
-use Cake\Console\Arguments;
-use Cake\Console\ConsoleIo;
 use Cake\Core\Configure;
 use Cake\Core\Plugin;
 use Cake\Utility\Filesystem;
@@ -31,20 +29,6 @@
  */
 trait PluginAssetsTrait
 {
-    /**
-     * Arguments
-     *
-     * @var \Cake\Console\Arguments
-     */
-    protected Arguments $args;
-
-    /**
-     * Console IO
-     *
-     * @var \Cake\Console\ConsoleIo
-     */
-    protected ConsoleIo $io;
-
     /**
      * Get list of plugins to process. Plugins without a webroot directory are skipped.
      *
diff --git a/src/Console/BaseCommand.php b/src/Console/BaseCommand.php
index 7cb40cff579..6687600c16e 100644
--- a/src/Console/BaseCommand.php
+++ b/src/Console/BaseCommand.php
@@ -61,6 +61,10 @@ abstract class BaseCommand implements CommandInterface, EventDispatcherInterface
      */
     protected string $name = 'cake unknown';
 
+    protected Arguments $args;
+
+    protected ConsoleIo $io;
+
     protected ?CommandFactoryInterface $factory = null;
 
     /**
@@ -170,8 +174,9 @@ protected function buildOptionParser(ConsoleOptionParser $parser): ConsoleOption
      * Hook method invoked by CakePHP when a command is about to be executed.
      *
      * Override this method and implement expensive/important setup steps that
-     * should not run on every command run. This method will be called *before*
-     * the options and arguments are validated and processed.
+     * should not run on every command run. This method will be called *after*
+     * the options and arguments are validated and processed, so `$this->args`
+     * and `$this->io` are both available.
      *
      * @return void
      */
@@ -227,7 +232,7 @@ public function afterExecute(EventInterface $event, Arguments $args, ConsoleIo $
      */
     public function run(array $argv, ConsoleIo $io): ?int
     {
-        $this->initialize();
+        $this->io = $io;
 
         $parser = $this->getOptionParser();
         try {
@@ -242,7 +247,10 @@ public function run(array $argv, ConsoleIo $io): ?int
 
             return static::CODE_ERROR;
         }
+        $this->args = $args;
+
         $this->setOutputLevel($args, $io);
+        $this->initialize();
 
         if ($args->getOption('help')) {
             $this->displayHelp($parser, $args, $io);
diff --git a/src/Console/Command/HelpCommand.php b/src/Console/Command/HelpCommand.php
index 366d09b69a5..b1613c787b4 100644
--- a/src/Console/Command/HelpCommand.php
+++ b/src/Console/Command/HelpCommand.php
@@ -33,7 +33,7 @@
 /**
  * Print out command list
  */
-class HelpCommand extends BaseCommand implements CommandCollectionAwareInterface
+class HelpCommand extends BaseCommand implements CommandCollectionAwareInterface, CommandHiddenInterface
 {
     /**
      * The command collection to get help on.
@@ -42,6 +42,13 @@ class HelpCommand extends BaseCommand implements CommandCollectionAwareInterface
      */
     protected CommandCollection $commands;
 
+    /**
+     * The header line rendered above command listings.
+     *
+     * @var string|null
+     */
+    protected ?string $headerLine = null;
+
     /**
      * @inheritDoc
      */
@@ -50,6 +57,17 @@ public function setCommandCollection(CommandCollection $commands): void
         $this->commands = $commands;
     }
 
+    /**
+     * Set the header line rendered above command listings.
+     *
+     * @param string $headerLine Header text including optional console markup.
+     * @return void
+     */
+    public function setHeaderLine(string $headerLine): void
+    {
+        $this->headerLine = $headerLine;
+    }
+
     /**
      * Main function Prints out the list of commands.
      *
@@ -143,10 +161,12 @@ protected function asText(ConsoleIo $io, iterable $commands, bool $verbose = fal
         }
         sort($commandList);
 
+        $headerLine = $this->getHeaderLine();
+        if ($headerLine !== '') {
+            $io->out($headerLine, 2);
+        }
+
         if ($verbose) {
-            $version = Configure::version();
-            $debug = Configure::read('debug') ? 'true' : 'false';
-            $io->out("<info>CakePHP:</info> {$version} (debug: {$debug})", 2);
             $this->outputPaths($io);
             $this->outputGrouped($io, $invert);
         } else {
@@ -164,6 +184,27 @@ protected function asText(ConsoleIo $io, iterable $commands, bool $verbose = fal
         }
     }
 
+    /**
+     * Get the help output header line.
+     *
+     * @return string
+     */
+    protected function getHeaderLine(): string
+    {
+        if ($this->headerLine !== null) {
+            return $this->headerLine;
+        }
+
+        $version = Configure::version();
+        if ($version === 'unknown') {
+            return '';
+        }
+
+        $debug = Configure::read('debug') ? 'true' : 'false';
+
+        return "<info>CakePHP:</info> {$version} (debug: {$debug})";
+    }
+
     /**
      * Output commands grouped by plugin/namespace (verbose mode).
      *
@@ -212,7 +253,7 @@ protected function outputGrouped(ConsoleIo $io, array $invert): void
             $io->out("<info>{$prefix}</info>:");
             sort($names);
             foreach ($names as $data) {
-                $io->out(' - ' . $data['name']);
+                $io->out(' - <comment>' . $data['name'] . '</comment>');
                 if ($data['description']) {
                     $io->info(str_pad(" \u{2514}", 13, "\u{2500}") . ' ' . $data['description']);
                 }
@@ -263,7 +304,7 @@ protected function outputCompactCommands(ConsoleIo $io, array $commands): void
         foreach ($commands as $data) {
             $maxNameLength = max($maxNameLength, strlen($data['name']));
         }
-        $nameColumnWidth = $maxNameLength + 3;
+        $nameColumnWidth = max($maxNameLength + 5, 17);
 
         // Output single commands under "Available Commands:" header
         $isFirst = true;
@@ -272,7 +313,7 @@ protected function outputCompactCommands(ConsoleIo $io, array $commands): void
             foreach ($singleCommands as $prefix => $cmd) {
                 $description = $cmd['description'];
                 $padding = str_repeat(' ', $nameColumnWidth - 2 - strlen($prefix));
-                $linePrefix = '  <info>' . $prefix . '</info>' . $padding;
+                $linePrefix = '  <comment>' . $prefix . '</comment>' . $padding;
 
                 if ($description !== '') {
                     $description = strtok($description, "\n");
@@ -296,7 +337,7 @@ protected function outputCompactCommands(ConsoleIo $io, array $commands): void
                 $description = $cmd['description'];
 
                 $padding = str_repeat(' ', $nameColumnWidth - 2 - strlen($fullName));
-                $linePrefix = '  <info>' . $fullName . '</info>' . $padding;
+                $linePrefix = '  <comment>' . $fullName . '</comment>' . $padding;
 
                 if ($description !== '') {
                     $description = strtok($description, "\n");
diff --git a/src/Console/CommandRunner.php b/src/Console/CommandRunner.php
index e1b3c40149f..4d6c2eaf3cb 100644
--- a/src/Console/CommandRunner.php
+++ b/src/Console/CommandRunner.php
@@ -21,6 +21,7 @@
 use Cake\Console\Exception\MissingOptionException;
 use Cake\Console\Exception\StopException;
 use Cake\Core\ConsoleApplicationInterface;
+use Cake\Core\ConsoleHelpHeaderProviderInterface;
 use Cake\Core\ContainerApplicationInterface;
 use Cake\Core\EventAwareApplicationInterface;
 use Cake\Core\PluginApplicationInterface;
@@ -262,6 +263,10 @@ protected function getCommand(ConsoleIo $io, CommandCollection $commands, string
             $instance = $this->createCommand($instance);
         }
 
+        if ($instance instanceof HelpCommand && $this->app instanceof ConsoleHelpHeaderProviderInterface) {
+            $instance->setHeaderLine($this->app->getConsoleHelpHeader());
+        }
+
         $instance->setName("{$this->root} {$name}");
 
         if ($instance instanceof CommandCollectionAwareInterface) {
@@ -320,7 +325,6 @@ protected function longestCommandName(CommandCollection $commands, array $argv):
     protected function resolveName(CommandCollection $commands, ConsoleIo $io, ?string $name): string
     {
         if (!$name) {
-            $io->error('No command provided. Choose one of the available commands.', 2);
             $name = 'help';
         }
         $name = $this->aliases[$name] ?? $name;
diff --git a/src/Console/CommandScanner.php b/src/Console/CommandScanner.php
index 3dd77883830..dadc7c35628 100644
--- a/src/Console/CommandScanner.php
+++ b/src/Console/CommandScanner.php
@@ -19,7 +19,7 @@
 use Cake\Core\App;
 use Cake\Core\Configure;
 use Cake\Core\Plugin;
-use Cake\Utility\Filesystem;
+use Cake\Utility\Fs\Finder;
 use Cake\Utility\Inflector;
 use ReflectionClass;
 
@@ -101,9 +101,12 @@ protected function scanDir(string $path, string $namespace, string $prefix, arra
         $hide[] = '';
 
         $classPattern = '/Command\.php$/';
-        $fs = new Filesystem();
         /** @var \Iterator<\SplFileInfo> $files */
-        $files = $fs->find($path, $classPattern);
+        $files = (new Finder())
+            ->in($path)
+            ->recursive(false)
+            ->name('*Command.php')
+            ->files();
 
         $commands = [];
         foreach ($files as $fileInfo) {
diff --git a/src/Console/Helper/BannerHelper.php b/src/Console/Helper/BannerHelper.php
new file mode 100644
index 00000000000..d34e26aeaff
--- /dev/null
+++ b/src/Console/Helper/BannerHelper.php
@@ -0,0 +1,111 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP Project
+ * @since         5.1.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Console\Helper;
+
+use Cake\Console\Helper;
+use InvalidArgumentException;
+
+/**
+ * Banner command helper.
+ *
+ * Formats one or more lines of text into a large banner with
+ * padding and a blank line below.
+ */
+class BannerHelper extends Helper
+{
+    /**
+     * @var int The horizontal padding that is added to the longest line.
+     */
+    private int $padding = 2;
+
+    /**
+     * @var string The console output style to use on the banner.
+     */
+    private string $style = 'success.bg';
+
+    /**
+     * Modify the padding of the helper
+     *
+     * @param int $padding The padding value to use.
+     * @return $this
+     */
+    public function withPadding(int $padding)
+    {
+        if ($padding < 0) {
+            throw new InvalidArgumentException('padding must be greater than 0');
+        }
+        $this->padding = $padding;
+
+        return $this;
+    }
+
+    /**
+     * Modify the padding of the helper
+     *
+     * @param string $style The style value to use.
+     * @return $this
+     */
+    public function withStyle(string $style)
+    {
+        $this->style = $style;
+
+        return $this;
+    }
+
+    /**
+     * Output a banner
+     *
+     * @param array $args The messages to output
+     * @return void
+     */
+    public function output(array $args): void
+    {
+        if ($args === []) {
+            throw new InvalidArgumentException('At least one argument is required');
+        }
+
+        $lengths = array_map(mb_strlen(...), $args);
+        $maxLength = max($lengths);
+        $bannerLength = $maxLength + $this->padding * 2;
+        $start = "<{$this->style}>";
+        $end = "</{$this->style}>";
+
+        $lines = [
+            '',
+            $start . str_repeat(' ', $bannerLength) . $end,
+        ];
+        foreach ($args as $line) {
+            $lineLength = mb_strlen($line);
+            $linePadding = (int)max($this->padding, $bannerLength - $lineLength - $this->padding);
+
+            $lines[] = $start .
+                str_repeat(' ', $this->padding) .
+                $line .
+                str_repeat(' ', $linePadding) .
+                $end;
+        }
+
+        $lines[] = $start . str_repeat(' ', $bannerLength) . $end;
+        $lines[] = '';
+
+        $this->_io->out($lines);
+    }
+}
+
+// phpcs:disable
+class_alias('Cake\Console\Helper\BannerHelper', 'Cake\Command\Helper\BannerHelper');
+// phpcs:enable
diff --git a/src/Console/Helper/ProgressHelper.php b/src/Console/Helper/ProgressHelper.php
new file mode 100644
index 00000000000..1d9077f28a5
--- /dev/null
+++ b/src/Console/Helper/ProgressHelper.php
@@ -0,0 +1,167 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP Project
+ * @since         3.1.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Console\Helper;
+
+use Cake\Console\Helper;
+use InvalidArgumentException;
+
+/**
+ * Create a progress bar using a supplied callback.
+ *
+ * ## Usage
+ *
+ * The ProgressHelper can be accessed from shells using the helper() method
+ *
+ * ```
+ * $this->helper('Progress')->output(['callback' => function ($progress) {
+ *     // Do work
+ *     $progress->increment();
+ * }]);
+ * ```
+ */
+class ProgressHelper extends Helper
+{
+    /**
+     * Default value for progress bar total value.
+     * Percent completion is derived from progress/total
+     */
+    protected const DEFAULT_TOTAL = 100;
+
+    /**
+     * Default value for progress bar width
+     */
+    protected const DEFAULT_WIDTH = 80;
+
+    /**
+     * The current progress.
+     *
+     * @var float|int
+     */
+    protected float|int $_progress = 0;
+
+    /**
+     * The total number of 'items' to progress through.
+     *
+     * @var int
+     */
+    protected int $_total = self::DEFAULT_TOTAL;
+
+    /**
+     * The width of the bar.
+     *
+     * @var int
+     */
+    protected int $_width = self::DEFAULT_WIDTH;
+
+    /**
+     * Output a progress bar.
+     *
+     * Takes a number of options to customize the behavior:
+     *
+     * - `total` The total number of items in the progress bar. Defaults
+     *   to 100.
+     * - `width` The width of the progress bar. Defaults to 80.
+     * - `callback` The callback that will be called in a loop to advance the progress bar.
+     *
+     * @param array $args The arguments/options to use when outputting the progress bar.
+     * @return void
+     */
+    public function output(array $args): void
+    {
+        $args += ['callback' => null];
+        if (isset($args[0])) {
+            $args['callback'] = $args[0];
+        }
+        if (!$args['callback'] || !is_callable($args['callback'])) {
+            throw new InvalidArgumentException('Callback option must be a callable.');
+        }
+        $this->init($args);
+
+        $callback = $args['callback'];
+
+        $this->_io->out('', 0);
+        while ($this->_progress < $this->_total) {
+            $callback($this);
+            $this->draw();
+        }
+        $this->_io->out('');
+    }
+
+    /**
+     * Initialize the progress bar for use.
+     *
+     * - `total` The total number of items in the progress bar. Defaults
+     *   to 100.
+     * - `width` The width of the progress bar. Defaults to 80.
+     *
+     * @param array<string, mixed> $args The initialization data.
+     * @return $this
+     */
+    public function init(array $args = [])
+    {
+        $args += ['total' => self::DEFAULT_TOTAL, 'width' => self::DEFAULT_WIDTH];
+        $this->_progress = 0;
+        $this->_width = $args['width'];
+        $this->_total = $args['total'];
+
+        return $this;
+    }
+
+    /**
+     * Increment the progress bar.
+     *
+     * @param float|int $num The amount of progress to advance by.
+     * @return $this
+     */
+    public function increment(float|int $num = 1)
+    {
+        $this->_progress = min(max(0, $this->_progress + $num), $this->_total);
+
+        return $this;
+    }
+
+    /**
+     * Render the progress bar based on the current state.
+     *
+     * @return $this
+     */
+    public function draw()
+    {
+        $numberLen = strlen(' 100%');
+        $complete = round($this->_progress / $this->_total, 2);
+        $barLen = ($this->_width - $numberLen) * $this->_progress / $this->_total;
+        $bar = '';
+        if ($barLen > 1) {
+            $bar = str_repeat('=', (int)$barLen - 1) . '>';
+        }
+
+        $pad = ceil($this->_width - $numberLen - $barLen);
+        if ($pad > 0) {
+            $bar .= str_repeat(' ', (int)$pad);
+        }
+        $percent = ($complete * 100) . '%';
+        $bar .= str_pad($percent, $numberLen, ' ', STR_PAD_LEFT);
+
+        $this->_io->overwrite($bar, 0);
+
+        return $this;
+    }
+}
+
+// phpcs:disable
+class_alias('Cake\Console\Helper\ProgressHelper', 'Cake\Command\Helper\ProgressHelper');
+// phpcs:enable
diff --git a/src/Console/Helper/TableHelper.php b/src/Console/Helper/TableHelper.php
new file mode 100644
index 00000000000..6d2606a5c5c
--- /dev/null
+++ b/src/Console/Helper/TableHelper.php
@@ -0,0 +1,189 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @since         3.1.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Console\Helper;
+
+use Cake\Console\Helper;
+use UnexpectedValueException;
+
+/**
+ * Create a visually pleasing ASCII art table
+ * from 2-dimensional array data.
+ */
+class TableHelper extends Helper
+{
+    /**
+     * Default config for this helper.
+     *
+     * @var array<string, mixed>
+     */
+    protected array $_defaultConfig = [
+        'headers' => true,
+        'rowSeparator' => false,
+        'headerStyle' => 'info',
+    ];
+
+    /**
+     * Calculate the column widths
+     *
+     * @param array $rows The rows on which the column's width will be calculated on.
+     * @return array<int>
+     */
+    protected function _calculateWidths(array $rows): array
+    {
+        $widths = [];
+        foreach ($rows as $line) {
+            foreach (array_values($line) as $k => $v) {
+                $columnLength = $this->_cellWidth((string)$v);
+                if ($columnLength >= ($widths[$k] ?? 0)) {
+                    $widths[$k] = $columnLength;
+                }
+            }
+        }
+
+        return $widths;
+    }
+
+    /**
+     * Get the width of a cell exclusive of style tags.
+     *
+     * @param string $text The text to calculate a width for.
+     * @return int The width of the textual content in visible characters.
+     */
+    protected function _cellWidth(string $text): int
+    {
+        if ($text === '') {
+            return 0;
+        }
+
+        if (!str_contains($text, '<') && !str_contains($text, '>')) {
+            return mb_strwidth($text);
+        }
+
+        $styles = $this->_io->styles();
+        $tags = implode('|', array_keys($styles));
+        $text = (string)preg_replace('#</?(?:' . $tags . ')>#', '', $text);
+
+        return mb_strwidth($text);
+    }
+
+    /**
+     * Output a row separator.
+     *
+     * @param array<int> $widths The widths of each column to output.
+     * @return void
+     */
+    protected function _rowSeparator(array $widths): void
+    {
+        $out = '';
+        foreach ($widths as $column) {
+            $out .= '+' . str_repeat('-', $column + 2);
+        }
+        $out .= '+';
+        $this->_io->out($out);
+    }
+
+    /**
+     * Output a row.
+     *
+     * @param array $row The row to output.
+     * @param array<int> $widths The widths of each column to output.
+     * @param array<string, mixed> $options Options to be passed.
+     * @return void
+     */
+    protected function _render(array $row, array $widths, array $options = []): void
+    {
+        if ($row === []) {
+            return;
+        }
+
+        $out = '';
+        foreach (array_values($row) as $i => $column) {
+            $column = (string)$column;
+            $pad = $widths[$i] - $this->_cellWidth($column);
+            if (!empty($options['style'])) {
+                $column = $this->_addStyle($column, $options['style']);
+            }
+            if ($column !== '' && preg_match('#(.*)<text-right>.+</text-right>(.*)#', $column, $matches)) {
+                if ($matches[1] !== '' || $matches[2] !== '') {
+                    throw new UnexpectedValueException('You cannot include text before or after the text-right tag.');
+                }
+                $column = str_replace(['<text-right>', '</text-right>'], '', $column);
+                $out .= '| ' . str_repeat(' ', $pad) . $column . ' ';
+            } else {
+                $out .= '| ' . $column . str_repeat(' ', $pad) . ' ';
+            }
+        }
+        $out .= '|';
+        $this->_io->out($out);
+    }
+
+    /**
+     * Output a table.
+     *
+     * Data will be output based on the order of the values
+     * in the array. The keys will not be used to align data.
+     *
+     * @param array $args The data to render out.
+     * @return void
+     */
+    public function output(array $args): void
+    {
+        if (!$args) {
+            return;
+        }
+
+        $this->_io->setStyle('text-right', ['text' => null]);
+
+        $config = $this->getConfig();
+        $widths = $this->_calculateWidths($args);
+
+        $this->_rowSeparator($widths);
+        if ($config['headers'] === true) {
+            $this->_render(array_shift($args), $widths, ['style' => $config['headerStyle']]);
+            $this->_rowSeparator($widths);
+        }
+
+        if (!$args) {
+            return;
+        }
+
+        foreach ($args as $line) {
+            $this->_render($line, $widths);
+            if ($config['rowSeparator'] === true) {
+                $this->_rowSeparator($widths);
+            }
+        }
+        if ($config['rowSeparator'] !== true) {
+            $this->_rowSeparator($widths);
+        }
+    }
+
+    /**
+     * Add style tags
+     *
+     * @param string $text The text to be surrounded
+     * @param string $style The style to be applied
+     * @return string
+     */
+    protected function _addStyle(string $text, string $style): string
+    {
+        return '<' . $style . '>' . $text . '</' . $style . '>';
+    }
+}
+
+// phpcs:disable
+class_alias('Cake\Console\Helper\TableHelper', 'Cake\Command\Helper\TableHelper');
+// phpcs:enable
diff --git a/src/Console/Helper/TreeHelper.php b/src/Console/Helper/TreeHelper.php
new file mode 100644
index 00000000000..c6ea47ba428
--- /dev/null
+++ b/src/Console/Helper/TreeHelper.php
@@ -0,0 +1,128 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP Project
+ * @since         5.3.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Console\Helper;
+
+use BackedEnum;
+use Cake\Console\Helper;
+use Cake\Database\Type\EnumLabelInterface;
+use Closure;
+use UnitEnum;
+
+/**
+ * Tree command helper.
+ *
+ * Formats nested arrays into a tree with dashes and pipes.
+ */
+class TreeHelper extends Helper
+{
+    /**
+     * @inheritDoc
+     */
+    protected array $_defaultConfig = [
+        'baseIndent' => 0,
+        'elementIndent' => 0,
+    ];
+
+    /**
+     * Outputs an array in tree form.
+     *
+     * @param array $args Tree array
+     * @return void
+     */
+    public function output(array $args): void
+    {
+        $prefix = str_repeat(' ', $this->_config['baseIndent']);
+        $this->outputArray($args, $prefix, topLevel: true);
+    }
+
+    /**
+     * Output an array in a tree.
+     *
+     * @param array $array
+     * @param string $prefix
+     * @param bool $topLevel
+     * @return void
+     */
+    protected function outputArray(array $array, string $prefix, bool $topLevel): void
+    {
+        $i = 1;
+        $numValues = count($array);
+        $elementPrefix = $topLevel ? '' : str_repeat(' ', $this->_config['elementIndent']);
+        foreach ($array as $key => $value) {
+            $isLast = $i++ === $numValues;
+            $marker = $isLast ? '└── ' : '├── ';
+            $indent = $isLast ? '    ' : '│   ';
+            $this->outputElement($key, $value, $prefix . $elementPrefix, $marker, $indent);
+        }
+    }
+
+    /**
+     * Output an array element.
+     *
+     * @param string|int $key
+     * @param mixed $value
+     * @param string $prefix
+     * @param string $marker
+     * @param string $indent
+     * @return void
+     */
+    protected function outputElement(
+        string|int $key,
+        mixed $value,
+        string $prefix,
+        string $marker,
+        string $indent,
+    ): void {
+        if (is_array($value)) {
+            $this->_io->out($prefix . $marker . $key);
+            $this->outputArray($value, $prefix . $indent, topLevel: false);
+        } elseif (is_string($key)) {
+            $this->_io->out($prefix . $marker . $key);
+            $this->outputValue($value, $prefix . $indent . '└── ');
+        } else {
+            $this->outputValue($value, $prefix . $marker);
+        }
+    }
+
+    /**
+     * Output a value in a tree.
+     *
+     * @param mixed $value
+     * @param string $prefix
+     * @return void
+     */
+    protected function outputValue(mixed $value, string $prefix): void
+    {
+        if ($value instanceof Closure) {
+            $this->_io->out($prefix . $value());
+        } elseif (interface_exists(EnumLabelInterface::class) && $value instanceof EnumLabelInterface) {
+            $this->_io->out($prefix . $value->label());
+        } elseif ($value instanceof BackedEnum) {
+            $this->_io->out($prefix . $value->value);
+        } elseif ($value instanceof UnitEnum) {
+            $this->_io->out($prefix . $value->name);
+        } elseif (is_bool($value)) {
+            $this->_io->out($prefix . ($value ? 'true' : 'false'));
+        } else {
+            $this->_io->out($prefix . $value);
+        }
+    }
+}
+
+// phpcs:disable
+class_alias('Cake\Console\Helper\TreeHelper', 'Cake\Command\Helper\TreeHelper');
+// phpcs:enable
diff --git a/src/Console/HelperRegistry.php b/src/Console/HelperRegistry.php
index dc6be8b042a..e3672c684c2 100644
--- a/src/Console/HelperRegistry.php
+++ b/src/Console/HelperRegistry.php
@@ -19,6 +19,7 @@
 use Cake\Console\Exception\MissingHelperException;
 use Cake\Core\App;
 use Cake\Core\ObjectRegistry;
+use function Cake\Core\deprecationWarning;
 
 /**
  * Registry for Helpers. Provides features
@@ -56,8 +57,25 @@ public function setIo(ConsoleIo $io): void
      */
     protected function _resolveClassName(string $class): ?string
     {
-        /** @var class-string<\Cake\Console\Helper>|null */
-        return App::className($class, 'Command/Helper', 'Helper');
+        /** @var class-string<\Cake\Console\Helper>|null $result */
+        $result = App::className($class, 'Console/Helper', 'Helper');
+        if ($result !== null) {
+            return $result;
+        }
+
+        /** @var class-string<\Cake\Console\Helper>|null $result */
+        $result = App::className($class, 'Command/Helper', 'Helper');
+        if ($result !== null) {
+            deprecationWarning(
+                '5.4.0',
+                sprintf(
+                    'Helpers in `Command/Helper` are deprecated. Move `%s` to `Console/Helper`.',
+                    $class,
+                ),
+            );
+        }
+
+        return $result;
     }
 
     /**
diff --git a/src/Console/composer.json b/src/Console/composer.json
index e66ee881434..c00fbd72c9f 100644
--- a/src/Console/composer.json
+++ b/src/Console/composer.json
@@ -24,10 +24,10 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
-        "cakephp/event": "^5.3.0",
-        "cakephp/log": "^5.3.0",
-        "cakephp/utility": "^5.3.0"
+        "cakephp/core": "5.4.*@dev",
+        "cakephp/event": "5.4.*@dev",
+        "cakephp/log": "5.4.*@dev",
+        "cakephp/utility": "5.4.*@dev"
     },
     "suggest": {
         "cakephp/datasource": "To use the Command base classes",
diff --git a/src/Container/Argument/ArgumentInterface.php b/src/Container/Argument/ArgumentInterface.php
new file mode 100644
index 00000000000..ab592c43524
--- /dev/null
+++ b/src/Container/Argument/ArgumentInterface.php
@@ -0,0 +1,12 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+interface ArgumentInterface
+{
+    /**
+     * @return mixed
+     */
+    public function getValue(): mixed;
+}
diff --git a/src/Container/Argument/ArgumentResolverInterface.php b/src/Container/Argument/ArgumentResolverInterface.php
new file mode 100644
index 00000000000..626a9ca2088
--- /dev/null
+++ b/src/Container/Argument/ArgumentResolverInterface.php
@@ -0,0 +1,23 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+use Cake\Container\ContainerAwareInterface;
+use ReflectionFunctionAbstract;
+
+interface ArgumentResolverInterface extends ContainerAwareInterface
+{
+    /**
+     * @param array<\Cake\Container\Argument\LiteralArgument|\Cake\Container\Argument\ResolvableArgument> $arguments
+     * @return array
+     */
+    public function resolveArguments(array $arguments): array;
+
+    /**
+     * @param \ReflectionFunctionAbstract $method
+     * @param array $args
+     * @return array
+     */
+    public function reflectArguments(ReflectionFunctionAbstract $method, array $args = []): array;
+}
diff --git a/src/Container/Argument/ArgumentResolverTrait.php b/src/Container/Argument/ArgumentResolverTrait.php
new file mode 100644
index 00000000000..049c9061ea5
--- /dev/null
+++ b/src/Container/Argument/ArgumentResolverTrait.php
@@ -0,0 +1,120 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+use Cake\Container\DefinitionContainerInterface;
+use Cake\Container\Exception\ContainerException;
+use Cake\Container\Exception\NotFoundException;
+use Cake\Container\ReflectionContainer;
+use Psr\Container\ContainerInterface;
+use ReflectionFunctionAbstract;
+use ReflectionNamedType;
+
+trait ArgumentResolverTrait
+{
+    /**
+     * @inheritDoc
+     */
+    public function resolveArguments(array $arguments): array
+    {
+        try {
+            $container = $this->getContainer();
+        } catch (ContainerException) {
+            $container = $this instanceof ReflectionContainer ? $this : null;
+        }
+
+        foreach ($arguments as &$arg) {
+            // if we have a literal, we don't want to do anything more with it
+            if ($arg instanceof LiteralArgumentInterface) {
+                $arg = $arg->getValue();
+                continue;
+            }
+
+            if ($arg instanceof ArgumentInterface) {
+                $argValue = $arg->getValue();
+            } else {
+                $argValue = $arg;
+            }
+
+            if (!is_string($argValue)) {
+                 continue;
+            }
+
+            // resolve the argument from the container, if it happens to be another
+            // argument wrapper, use that value
+            if ($container instanceof ContainerInterface && $container->has($argValue)) {
+                try {
+                    $arg = $container->get($argValue);
+
+                    if ($arg instanceof ArgumentInterface) {
+                        $arg = $arg->getValue();
+                    }
+
+                    continue;
+                } catch (NotFoundException) {
+                }
+            }
+
+            // if we have a default value, we use that, no more resolution as
+            // we expect a default/optional argument value to be literal
+            if ($arg instanceof DefaultValueInterface) {
+                $arg = $arg->getDefaultValue();
+            }
+        }
+
+        return $arguments;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function reflectArguments(ReflectionFunctionAbstract $method, array $args = []): array
+    {
+        $params = $method->getParameters();
+        $arguments = [];
+
+        foreach ($params as $param) {
+            $name = $param->getName();
+
+            // if we've been given a value for the argument, treat as literal
+            if (array_key_exists($name, $args)) {
+                $arguments[] = new LiteralArgument($args[$name]);
+                continue;
+            }
+
+            $type = $param->getType();
+
+            if ($type instanceof ReflectionNamedType) {
+                // in PHP 8, nullable arguments have "?" prefix
+                $typeHint = ltrim($type->getName(), '?');
+
+                if ($param->isDefaultValueAvailable()) {
+                    $arguments[] = new DefaultValueArgument($typeHint, $param->getDefaultValue());
+                    continue;
+                }
+
+                $arguments[] = new ResolvableArgument($typeHint);
+                continue;
+            }
+
+            if ($param->isDefaultValueAvailable()) {
+                $arguments[] = new LiteralArgument($param->getDefaultValue());
+                continue;
+            }
+
+            throw new NotFoundException(sprintf(
+                'Unable to resolve a value for parameter (%s) in the function/method (%s)',
+                $name,
+                $method->getName(),
+            ));
+        }
+
+        return $this->resolveArguments($arguments);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    abstract public function getContainer(): DefinitionContainerInterface;
+}
diff --git a/src/Container/Argument/DefaultValueArgument.php b/src/Container/Argument/DefaultValueArgument.php
new file mode 100644
index 00000000000..8616c870c80
--- /dev/null
+++ b/src/Container/Argument/DefaultValueArgument.php
@@ -0,0 +1,27 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+class DefaultValueArgument extends ResolvableArgument implements DefaultValueInterface
+{
+    protected mixed $defaultValue;
+
+    /**
+     * @param string $value
+     * @param mixed|null $defaultValue
+     */
+    public function __construct(string $value, mixed $defaultValue = null)
+    {
+        $this->defaultValue = $defaultValue;
+        parent::__construct($value);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getDefaultValue(): mixed
+    {
+        return $this->defaultValue;
+    }
+}
diff --git a/src/Container/Argument/DefaultValueInterface.php b/src/Container/Argument/DefaultValueInterface.php
new file mode 100644
index 00000000000..bfc764060b9
--- /dev/null
+++ b/src/Container/Argument/DefaultValueInterface.php
@@ -0,0 +1,12 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+interface DefaultValueInterface extends ArgumentInterface
+{
+    /**
+     * @return mixed
+     */
+    public function getDefaultValue(): mixed;
+}
diff --git a/src/Container/Argument/Literal/ArrayArgument.php b/src/Container/Argument/Literal/ArrayArgument.php
new file mode 100644
index 00000000000..d063c2d9c41
--- /dev/null
+++ b/src/Container/Argument/Literal/ArrayArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class ArrayArgument extends LiteralArgument
+{
+    /**
+     * @param array $value
+     */
+    public function __construct(array $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_ARRAY);
+    }
+}
diff --git a/src/Container/Argument/Literal/BooleanArgument.php b/src/Container/Argument/Literal/BooleanArgument.php
new file mode 100644
index 00000000000..e36e857ab70
--- /dev/null
+++ b/src/Container/Argument/Literal/BooleanArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class BooleanArgument extends LiteralArgument
+{
+    /**
+     * @param bool $value
+     */
+    public function __construct(bool $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_BOOL);
+    }
+}
diff --git a/src/Container/Argument/Literal/CallableArgument.php b/src/Container/Argument/Literal/CallableArgument.php
new file mode 100644
index 00000000000..6a2768a4974
--- /dev/null
+++ b/src/Container/Argument/Literal/CallableArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class CallableArgument extends LiteralArgument
+{
+    /**
+     * @param callable $value
+     */
+    public function __construct(callable $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_CALLABLE);
+    }
+}
diff --git a/src/Container/Argument/Literal/FloatArgument.php b/src/Container/Argument/Literal/FloatArgument.php
new file mode 100644
index 00000000000..4f532bfd83c
--- /dev/null
+++ b/src/Container/Argument/Literal/FloatArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class FloatArgument extends LiteralArgument
+{
+    /**
+     * @param float $value
+     */
+    public function __construct(float $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_FLOAT);
+    }
+}
diff --git a/src/Container/Argument/Literal/IntegerArgument.php b/src/Container/Argument/Literal/IntegerArgument.php
new file mode 100644
index 00000000000..6fd937ae0f5
--- /dev/null
+++ b/src/Container/Argument/Literal/IntegerArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class IntegerArgument extends LiteralArgument
+{
+    /**
+     * @param int $value
+     */
+    public function __construct(int $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_INT);
+    }
+}
diff --git a/src/Container/Argument/Literal/ObjectArgument.php b/src/Container/Argument/Literal/ObjectArgument.php
new file mode 100644
index 00000000000..f13f13b149f
--- /dev/null
+++ b/src/Container/Argument/Literal/ObjectArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class ObjectArgument extends LiteralArgument
+{
+    /**
+     * @param object $value
+     */
+    public function __construct(object $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_OBJECT);
+    }
+}
diff --git a/src/Container/Argument/Literal/StringArgument.php b/src/Container/Argument/Literal/StringArgument.php
new file mode 100644
index 00000000000..47973a35efd
--- /dev/null
+++ b/src/Container/Argument/Literal/StringArgument.php
@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument\Literal;
+
+use Cake\Container\Argument\LiteralArgument;
+
+class StringArgument extends LiteralArgument
+{
+    /**
+     * @param string $value
+     */
+    public function __construct(string $value)
+    {
+        parent::__construct($value, LiteralArgument::TYPE_STRING);
+    }
+}
diff --git a/src/Container/Argument/LiteralArgument.php b/src/Container/Argument/LiteralArgument.php
new file mode 100644
index 00000000000..df4ec0e928e
--- /dev/null
+++ b/src/Container/Argument/LiteralArgument.php
@@ -0,0 +1,51 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+use InvalidArgumentException;
+
+class LiteralArgument implements LiteralArgumentInterface
+{
+    public const TYPE_ARRAY = 'array';
+    public const TYPE_BOOL = 'boolean';
+    public const TYPE_BOOLEAN = 'boolean';
+    public const TYPE_CALLABLE = 'callable';
+    public const TYPE_DOUBLE = 'double';
+    public const TYPE_FLOAT = 'double';
+    public const TYPE_INT = 'integer';
+    public const TYPE_INTEGER = 'integer';
+    public const TYPE_OBJECT = 'object';
+    public const TYPE_STRING = 'string';
+
+    /**
+     * @var mixed
+     */
+    protected mixed $value;
+
+    /**
+     * @param mixed $value
+     * @param string|null $type
+     */
+    public function __construct(mixed $value, ?string $type = null)
+    {
+        if (
+            $type === null
+            || ($type === self::TYPE_CALLABLE && is_callable($value))
+            || ($type === self::TYPE_OBJECT && is_object($value))
+            || gettype($value) === $type
+        ) {
+            $this->value = $value;
+        } else {
+            throw new InvalidArgumentException('Incorrect type for value.');
+        }
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getValue(): mixed
+    {
+        return $this->value;
+    }
+}
diff --git a/src/Container/Argument/LiteralArgumentInterface.php b/src/Container/Argument/LiteralArgumentInterface.php
new file mode 100644
index 00000000000..a0238d0a6b0
--- /dev/null
+++ b/src/Container/Argument/LiteralArgumentInterface.php
@@ -0,0 +1,8 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+interface LiteralArgumentInterface extends ArgumentInterface
+{
+}
diff --git a/src/Container/Argument/ResolvableArgument.php b/src/Container/Argument/ResolvableArgument.php
new file mode 100644
index 00000000000..2ba30286d73
--- /dev/null
+++ b/src/Container/Argument/ResolvableArgument.php
@@ -0,0 +1,25 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+class ResolvableArgument implements ResolvableArgumentInterface
+{
+    protected string $value;
+
+    /**
+     * @param string $value
+     */
+    public function __construct(string $value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * @return string
+     */
+    public function getValue(): string
+    {
+        return $this->value;
+    }
+}
diff --git a/src/Container/Argument/ResolvableArgumentInterface.php b/src/Container/Argument/ResolvableArgumentInterface.php
new file mode 100644
index 00000000000..741e5864512
--- /dev/null
+++ b/src/Container/Argument/ResolvableArgumentInterface.php
@@ -0,0 +1,12 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Argument;
+
+interface ResolvableArgumentInterface extends ArgumentInterface
+{
+    /**
+     * @return string
+     */
+    public function getValue(): string;
+}
diff --git a/src/Container/Container.php b/src/Container/Container.php
new file mode 100644
index 00000000000..65a3694a96d
--- /dev/null
+++ b/src/Container/Container.php
@@ -0,0 +1,333 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container;
+
+use Cake\Container\Definition\DefinitionAggregate;
+use Cake\Container\Definition\DefinitionAggregateInterface;
+use Cake\Container\Definition\DefinitionInterface;
+use Cake\Container\Exception\ContainerException;
+use Cake\Container\Exception\NotFoundException;
+use Cake\Container\Inflector\InflectorAggregate;
+use Cake\Container\Inflector\InflectorAggregateInterface;
+use Cake\Container\Inflector\InflectorInterface;
+use Cake\Container\ServiceProvider\ServiceProviderAggregate;
+use Cake\Container\ServiceProvider\ServiceProviderAggregateInterface;
+use Cake\Container\ServiceProvider\ServiceProviderInterface;
+use Psr\Container\ContainerInterface;
+
+class Container implements DefinitionContainerInterface
+{
+    /**
+     * @var bool
+     */
+    protected bool $defaultToShared = false;
+
+    /**
+     * @var array<\Psr\Container\ContainerInterface>
+     */
+    protected array $delegates = [];
+
+    /**
+     * @param \Cake\Container\Definition\DefinitionAggregateInterface $definitions
+     * @param \Cake\Container\ServiceProvider\ServiceProviderAggregateInterface $providers
+     * @param \Cake\Container\Inflector\InflectorAggregateInterface $inflectors
+     */
+    public function __construct(
+        protected DefinitionAggregateInterface $definitions = new DefinitionAggregate(),
+        protected ServiceProviderAggregateInterface $providers = new ServiceProviderAggregate(),
+        protected InflectorAggregateInterface $inflectors = new InflectorAggregate(),
+    ) {
+        $this->definitions->setContainer($this);
+        $this->providers->setContainer($this);
+        $this->inflectors->setContainer($this);
+
+        $this->enableAutoWiring();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function add(string $id, $concrete = null): DefinitionInterface
+    {
+        $concrete ??= $id;
+
+        if ($this->defaultToShared) {
+            return $this->addShared($id, $concrete);
+        }
+
+        return $this->definitions->add($id, $concrete);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addShared(string $id, $concrete = null): DefinitionInterface
+    {
+        $concrete ??= $id;
+
+        return $this->definitions->addShared($id, $concrete);
+    }
+
+    /**
+     * Add multiple definitions at once.
+     *
+     * Examples:
+     *
+     * ```
+     * $container->addDefinitions([
+     *     Foo::class,
+     *     Bar::class
+     * ]);
+     * ```
+     *
+     * ```
+     * $container->addDefinitions([
+     *     Foo::class => [Bar::class],
+     *     Bar::class
+     * ]);
+     * ```
+     *
+     * ```
+     * $container->addDefinitions([
+     *    'foo' => Foo::class,
+     *    'bar' => Bar::class
+     * ]);
+     * ```
+     *
+     * @param array<int|string, array<class-string>|class-string> $definitions
+     * @return \Cake\Container\DefinitionContainerInterface
+     */
+    public function addDefinitions(array $definitions): DefinitionContainerInterface
+    {
+        foreach ($definitions as $id => $definition) {
+            if (is_int($id) && is_string($definition)) {
+                $this->add($definition);
+            } elseif (is_string($id) && is_string($definition)) {
+                $this->add($id, $definition);
+            } elseif (is_string($id) && is_array($definition)) {
+                $this->add($id)
+                    ->addArguments($definition);
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param bool $shared
+     * @return \Psr\Container\ContainerInterface
+     */
+    public function defaultToShared(bool $shared = true): ContainerInterface
+    {
+        $this->defaultToShared = $shared;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function extend(string $id): DefinitionInterface
+    {
+        if ($this->providers->provides($id)) {
+            $this->providers->register($id);
+        }
+
+        if ($this->definitions->has($id)) {
+            return $this->definitions->getDefinition($id);
+        }
+
+        throw new NotFoundException(sprintf(
+            'Unable to extend alias (%s) as it is not being managed as a definition',
+            $id,
+        ));
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addServiceProvider(ServiceProviderInterface $provider): DefinitionContainerInterface
+    {
+        $this->providers->add($provider);
+
+        return $this;
+    }
+
+    /**
+     * @template RequestedType
+     * @param class-string<RequestedType>|string $id
+     * @return RequestedType|mixed
+     * @throws \Psr\Container\ContainerExceptionInterface
+     * @throws \Psr\Container\NotFoundExceptionInterface
+     */
+    public function get(string $id)
+    {
+        return $this->resolve($id);
+    }
+
+    /**
+     * @template RequestedType
+     * @param class-string<RequestedType>|string $id
+     * @return RequestedType|mixed
+     * @throws \Psr\Container\ContainerExceptionInterface
+     * @throws \Psr\Container\NotFoundExceptionInterface
+     */
+    public function getNew(mixed $id): mixed
+    {
+        return $this->resolve($id, true);
+    }
+
+    /**
+     * Resolve an entry with specific constructor arguments.
+     *
+     * Unlike `get()`, this method allows passing specific constructor arguments
+     * that will be used during autowiring. Arguments can be passed by name.
+     *
+     * Example:
+     * ```
+     * $container->make(MyService::class, ['configValue' => 'foo']);
+     * ```
+     *
+     * @template RequestedType
+     * @param class-string<RequestedType>|string $id
+     * @param array<string, mixed> $args Named arguments to pass to the constructor
+     * @return RequestedType|mixed
+     * @throws \Psr\Container\ContainerExceptionInterface
+     * @throws \Psr\Container\NotFoundExceptionInterface
+     */
+    public function make(string $id, array $args = []): mixed
+    {
+        return $this->resolve($id, true, $args);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function has($id): bool
+    {
+        if ($this->definitions->has($id)) {
+            return true;
+        }
+
+        if ($this->definitions->hasTag($id)) {
+            return true;
+        }
+
+        if ($this->providers->provides($id)) {
+            return true;
+        }
+
+        foreach ($this->delegates as $delegate) {
+            if ($delegate->has($id)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function hasDefinition(string $id): bool
+    {
+        return $this->definitions->has($id);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function inflector(string $type, ?callable $callback = null): InflectorInterface
+    {
+        return $this->inflectors->add($type, $callback);
+    }
+
+    /**
+     * @param \Psr\Container\ContainerInterface $container
+     * @return $this
+     */
+    public function delegate(ContainerInterface $container)
+    {
+        $this->delegates[] = $container;
+
+        if ($container instanceof ContainerAwareInterface) {
+            $container->setContainer($this);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param bool $cache
+     * @return void
+     */
+    public function enableAutoWiring(bool $cache = true): void
+    {
+        $this->delegate(new ReflectionContainer($cache));
+    }
+
+    /**
+     * @return void
+     */
+    public function disableAutoWiring(): void
+    {
+        $this->delegates = [];
+    }
+
+    /**
+     * @param mixed $id
+     * @param bool $new
+     * @param array<string, mixed> $args
+     * @return mixed|object|array|null|void
+     * @throws \Psr\Container\ContainerExceptionInterface
+     * @throws \Psr\Container\NotFoundExceptionInterface
+     */
+    protected function resolve(mixed $id, bool $new = false, array $args = []): mixed
+    {
+        if ($this->definitions->has($id)) {
+            $resolved = $new ? $this->definitions->resolveNew($id) : $this->definitions->resolve($id);
+
+            return $this->inflectors->inflect($resolved);
+        }
+
+        if ($this->definitions->hasTag($id)) {
+            $arrayOf = $new
+                ? $this->definitions->resolveTaggedNew($id)
+                : $this->definitions->resolveTagged($id);
+
+            array_walk($arrayOf, function (object &$resolved): void {
+                $resolved = $this->inflectors->inflect($resolved);
+            });
+
+            return $arrayOf;
+        }
+
+        if ($this->providers->provides($id)) {
+            $this->providers->register($id);
+
+            if (!$this->definitions->has($id) && !$this->definitions->hasTag($id)) {
+                throw new ContainerException(sprintf('Service provider lied about providing (%s) service', $id));
+            }
+
+            return $this->resolve($id, $new, $args);
+        }
+
+        foreach ($this->delegates as $delegate) {
+            if ($delegate->has($id)) {
+                // Use getNew() for ReflectionContainer when $new is true or args are provided
+                if ($delegate instanceof ReflectionContainer) {
+                    $resolved = $new || $args !== []
+                        ? $delegate->getNew($id, $args)
+                        : $delegate->get($id, $args);
+                } else {
+                    $resolved = $delegate->get($id);
+                }
+
+                return $this->inflectors->inflect($resolved);
+            }
+        }
+
+        throw new NotFoundException(sprintf('Alias (%s) is not being managed by the container or delegates', $id));
+    }
+}
diff --git a/src/Container/ContainerAwareInterface.php b/src/Container/ContainerAwareInterface.php
new file mode 100644
index 00000000000..4817cc83ed7
--- /dev/null
+++ b/src/Container/ContainerAwareInterface.php
@@ -0,0 +1,18 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container;
+
+interface ContainerAwareInterface
+{
+    /**
+     * @return \Cake\Container\DefinitionContainerInterface
+     */
+    public function getContainer(): DefinitionContainerInterface;
+
+    /**
+     * @param \Cake\Container\DefinitionContainerInterface $container
+     * @return $this
+     */
+    public function setContainer(DefinitionContainerInterface $container): ContainerAwareInterface;
+}
diff --git a/src/Container/ContainerAwareTrait.php b/src/Container/ContainerAwareTrait.php
new file mode 100644
index 00000000000..cf7fc1a7ded
--- /dev/null
+++ b/src/Container/ContainerAwareTrait.php
@@ -0,0 +1,45 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container;
+
+use BadMethodCallException;
+use Cake\Container\Exception\ContainerException;
+
+trait ContainerAwareTrait
+{
+    /**
+     * @var \Cake\Container\DefinitionContainerInterface|null
+     */
+    protected ?DefinitionContainerInterface $container = null;
+
+    /**
+     * @inheritDoc
+     */
+    public function setContainer(DefinitionContainerInterface $container): ContainerAwareInterface
+    {
+        $this->container = $container;
+
+        if ($this instanceof ContainerAwareInterface) {
+            return $this;
+        }
+
+        throw new BadMethodCallException(sprintf(
+            'Attempt to use (%s) while not implementing (%s)',
+            ContainerAwareTrait::class,
+            ContainerAwareInterface::class,
+        ));
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getContainer(): DefinitionContainerInterface
+    {
+        if ($this->container instanceof DefinitionContainerInterface) {
+            return $this->container;
+        }
+
+        throw new ContainerException('No container implementation has been set.');
+    }
+}
diff --git a/src/Container/Definition/Definition.php b/src/Container/Definition/Definition.php
new file mode 100644
index 00000000000..ebf7f2b7410
--- /dev/null
+++ b/src/Container/Definition/Definition.php
@@ -0,0 +1,344 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Definition;
+
+use Cake\Container\Argument\ArgumentInterface;
+use Cake\Container\Argument\ArgumentResolverInterface;
+use Cake\Container\Argument\ArgumentResolverTrait;
+use Cake\Container\Argument\LiteralArgumentInterface;
+use Cake\Container\ContainerAwareTrait;
+use Cake\Container\Exception\ContainerException;
+use ReflectionClass;
+
+class Definition implements ArgumentResolverInterface, DefinitionInterface
+{
+    use ArgumentResolverTrait;
+    use ContainerAwareTrait;
+
+    /**
+     * @var string
+     */
+    protected string $alias;
+
+    /**
+     * @var mixed
+     */
+    protected mixed $concrete;
+
+    /**
+     * @var bool
+     */
+    protected bool $shared = false;
+
+    /**
+     * @var array
+     */
+    protected array $tags = [];
+
+    /**
+     * @var array
+     */
+    protected array $arguments = [];
+
+    /**
+     * @var array
+     */
+    protected array $methods = [];
+
+    /**
+     * @var mixed
+     */
+    protected mixed $resolved = null;
+
+    /**
+     * @var array
+     */
+    protected array $recursiveCheck = [];
+
+    /**
+     * @param string     $id
+     * @param mixed|null $concrete
+     */
+    public function __construct(string $id, mixed $concrete = null)
+    {
+        $id = static::normaliseAlias($id);
+
+        $concrete ??= $id;
+        $this->alias = $id;
+        $this->concrete = $concrete;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addTag(string $tag): DefinitionInterface
+    {
+        $this->tags[$tag] = true;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getTags(): array
+    {
+        return array_keys($this->tags);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function hasTag(string $tag): bool
+    {
+        return isset($this->tags[$tag]);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setAlias(string $id): DefinitionInterface
+    {
+        $id = static::normaliseAlias($id);
+
+        $this->alias = $id;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getAlias(): string
+    {
+        return $this->alias;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setShared(bool $shared = true): DefinitionInterface
+    {
+        $this->shared = $shared;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function isShared(): bool
+    {
+        return $this->shared;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getConcrete(): mixed
+    {
+        return $this->concrete;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setConcrete($concrete): DefinitionInterface
+    {
+        $this->concrete = $concrete;
+        $this->resolved = null;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addArgument($arg, ?string $name = null): DefinitionInterface
+    {
+        if ($name) {
+            $this->arguments[$name] = $arg;
+        } else {
+            $this->arguments[] = $arg;
+        }
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addArguments(array $args): DefinitionInterface
+    {
+        foreach ($args as $argName => $arg) {
+            if (is_string($argName)) {
+                $this->addArgument($arg, $argName);
+            } else {
+                $this->addArgument($arg);
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addMethodCall(string $method, array $args = []): DefinitionInterface
+    {
+        $this->methods[] = [
+            'method' => $method,
+            'arguments' => $args,
+        ];
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addMethodCalls(array $methods = []): DefinitionInterface
+    {
+        foreach ($methods as $method => $args) {
+            $this->addMethodCall($method, $args);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolve(): mixed
+    {
+        if ($this->resolved !== null && $this->isShared()) {
+            return $this->resolved;
+        }
+
+        return $this->resolveNew();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolveNew(): mixed
+    {
+        $concrete = $this->concrete;
+
+        if (is_callable($concrete)) {
+            $concrete = $this->resolveCallable($concrete);
+        }
+
+        if ($concrete instanceof LiteralArgumentInterface) {
+            $this->resolved = $concrete->getValue();
+
+            return $concrete->getValue();
+        }
+
+        if ($concrete instanceof ArgumentInterface) {
+            $concrete = $concrete->getValue();
+        }
+
+        // Check if the container has a registered definition for this concrete class
+        // before attempting to instantiate it directly. This ensures interface -> concrete
+        // bindings respect existing definitions for the concrete class (fixes #275, #278).
+        try {
+            $container = $this->getContainer();
+        } catch (ContainerException) {
+            $container = null;
+        }
+
+        if (
+            is_string($concrete)
+            && $concrete !== $this->alias
+            && $container !== null
+            && $container->hasDefinition($concrete)
+        ) {
+            $this->recursiveCheck[] = $concrete;
+            $concrete = $container->get($concrete);
+            $this->resolved = $concrete;
+
+            return $concrete;
+        }
+
+        if (is_string($concrete) && class_exists($concrete)) {
+            $concrete = $this->resolveClass($concrete);
+        }
+
+        if (is_object($concrete)) {
+            $concrete = $this->invokeMethods($concrete);
+        }
+
+        // stop recursive resolving
+        if (is_string($concrete) && in_array($concrete, $this->recursiveCheck)) {
+            $this->resolved = $concrete;
+
+            return $concrete;
+        }
+
+        // if we still have a string, try to pull it from the container
+        // this allows for `alias -> alias -> ... -> concrete
+        if (is_string($concrete) && $container !== null && $container->has($concrete)) {
+            $this->recursiveCheck[] = $concrete;
+            $concrete = $container->get($concrete);
+        }
+
+        $this->resolved = $concrete;
+
+        return $concrete;
+    }
+
+    /**
+     * @param callable $concrete
+     * @return mixed
+     */
+    protected function resolveCallable(callable $concrete): mixed
+    {
+        $resolved = $this->resolveArguments($this->arguments);
+
+        return call_user_func_array($concrete, $resolved);
+    }
+
+    /**
+     * @param class-string $concrete
+     * @return object
+     * @throws \ReflectionException
+     */
+    protected function resolveClass(string $concrete): object
+    {
+        $resolved = $this->resolveArguments($this->arguments);
+        $reflection = new ReflectionClass($concrete);
+
+        return $reflection->newInstanceArgs($resolved);
+    }
+
+    /**
+     * @param object $instance
+     * @return object
+     */
+    protected function invokeMethods(object $instance): object
+    {
+        foreach ($this->methods as $method) {
+            $args = $this->resolveArguments($method['arguments']);
+            /** @var callable $callable */
+            $callable = [$instance, $method['method']];
+            call_user_func_array($callable, $args);
+        }
+
+        return $instance;
+    }
+
+    /**
+     * @param string $alias
+     * @return string
+     */
+    public static function normaliseAlias(string $alias): string
+    {
+        if (str_starts_with($alias, '\\')) {
+            return substr($alias, 1);
+        }
+
+        return $alias;
+    }
+}
diff --git a/src/Container/Definition/DefinitionAggregate.php b/src/Container/Definition/DefinitionAggregate.php
new file mode 100644
index 00000000000..a57f4ef1f5c
--- /dev/null
+++ b/src/Container/Definition/DefinitionAggregate.php
@@ -0,0 +1,154 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Definition;
+
+use Cake\Container\ContainerAwareTrait;
+use Cake\Container\Exception\NotFoundException;
+use Generator;
+
+class DefinitionAggregate implements DefinitionAggregateInterface
+{
+    use ContainerAwareTrait;
+
+    /**
+     * @var array<\Cake\Container\Definition\DefinitionInterface>
+     */
+    protected array $definitions = [];
+
+    /**
+     * @param array $definitions
+     */
+    public function __construct(array $definitions = [])
+    {
+        $this->definitions = array_filter($definitions, static function ($definition) {
+            return $definition instanceof DefinitionInterface;
+        });
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function add(string $id, $definition): DefinitionInterface
+    {
+        if (!($definition instanceof DefinitionInterface)) {
+            $definition = new Definition($id, $definition);
+        }
+
+        $this->definitions[] = $definition->setAlias($id);
+
+        return $definition;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addShared(string $id, $definition): DefinitionInterface
+    {
+        $definition = $this->add($id, $definition);
+
+        return $definition->setShared(true);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function has(string $id): bool
+    {
+        $id = Definition::normaliseAlias($id);
+
+        foreach ($this->getIterator() as $definition) {
+            if ($id === $definition->getAlias()) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function hasTag(string $tag): bool
+    {
+        foreach ($this->getIterator() as $definition) {
+            if ($definition->hasTag($tag)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getDefinition(string $id): DefinitionInterface
+    {
+        $id = Definition::normaliseAlias($id);
+
+        foreach ($this->getIterator() as $definition) {
+            if ($id === $definition->getAlias()) {
+                return $definition->setContainer($this->getContainer());
+            }
+        }
+
+        throw new NotFoundException(sprintf('Alias (%s) is not being handled as a definition.', $id));
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolve(string $id): mixed
+    {
+        return $this->getDefinition($id)->resolve();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolveNew(string $id): mixed
+    {
+        return $this->getDefinition($id)->resolveNew();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolveTagged(string $tag): array
+    {
+        $arrayOf = [];
+
+        foreach ($this->getIterator() as $definition) {
+            if ($definition->hasTag($tag)) {
+                $arrayOf[] = $definition->setContainer($this->getContainer())->resolve();
+            }
+        }
+
+        return $arrayOf;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolveTaggedNew(string $tag): array
+    {
+        $arrayOf = [];
+
+        foreach ($this->getIterator() as $definition) {
+            if ($definition->hasTag($tag)) {
+                $arrayOf[] = $definition->setContainer($this->getContainer())->resolveNew();
+            }
+        }
+
+        return $arrayOf;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getIterator(): Generator
+    {
+        yield from $this->definitions;
+    }
+}
diff --git a/src/Container/Definition/DefinitionAggregateInterface.php b/src/Container/Definition/DefinitionAggregateInterface.php
new file mode 100644
index 00000000000..cb0dd079da0
--- /dev/null
+++ b/src/Container/Definition/DefinitionAggregateInterface.php
@@ -0,0 +1,69 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Definition;
+
+use Cake\Container\ContainerAwareInterface;
+use IteratorAggregate;
+
+/**
+ * @template-extends \IteratorAggregate<string, \Cake\Container\Definition\DefinitionInterface>
+ */
+interface DefinitionAggregateInterface extends ContainerAwareInterface, IteratorAggregate
+{
+    /**
+     * @param string $id
+     * @param mixed $definition
+     * @return \Cake\Container\Definition\DefinitionInterface
+     */
+    public function add(string $id, mixed $definition): DefinitionInterface;
+
+    /**
+     * @param string $id
+     * @param mixed $definition
+     * @return \Cake\Container\Definition\DefinitionInterface
+     */
+    public function addShared(string $id, mixed $definition): DefinitionInterface;
+
+    /**
+     * @param string $id
+     * @return \Cake\Container\Definition\DefinitionInterface
+     */
+    public function getDefinition(string $id): DefinitionInterface;
+
+    /**
+     * @param string $id
+     * @return bool
+     */
+    public function has(string $id): bool;
+
+    /**
+     * @param string $tag
+     * @return bool
+     */
+    public function hasTag(string $tag): bool;
+
+    /**
+     * @param string $id
+     * @return mixed
+     */
+    public function resolve(string $id): mixed;
+
+    /**
+     * @param string $id
+     * @return mixed
+     */
+    public function resolveNew(string $id): mixed;
+
+    /**
+     * @param string $tag
+     * @return array
+     */
+    public function resolveTagged(string $tag): array;
+
+    /**
+     * @param string $tag
+     * @return array
+     */
+    public function resolveTaggedNew(string $tag): array;
+}
diff --git a/src/Container/Definition/DefinitionInterface.php b/src/Container/Definition/DefinitionInterface.php
new file mode 100644
index 00000000000..e3996d8b33c
--- /dev/null
+++ b/src/Container/Definition/DefinitionInterface.php
@@ -0,0 +1,95 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Definition;
+
+use Cake\Container\ContainerAwareInterface;
+
+interface DefinitionInterface extends ContainerAwareInterface
+{
+    /**
+     * @param mixed $arg
+     * @param string|null $name
+     * @return $this
+     */
+    public function addArgument(mixed $arg, ?string $name = null): DefinitionInterface;
+
+    /**
+     * @param array $args
+     * @return $this
+     */
+    public function addArguments(array $args): DefinitionInterface;
+
+    /**
+     * @param string $method
+     * @param array $args
+     * @return $this
+     */
+    public function addMethodCall(string $method, array $args = []): DefinitionInterface;
+
+    /**
+     * @param array $methods
+     * @return $this
+     */
+    public function addMethodCalls(array $methods = []): DefinitionInterface;
+
+    /**
+     * @param string $tag
+     * @return $this
+     */
+    public function addTag(string $tag): DefinitionInterface;
+
+    /**
+     * @return string
+     */
+    public function getAlias(): string;
+
+    /**
+     * @return mixed
+     */
+    public function getConcrete(): mixed;
+
+    /**
+     * @return array<string>
+     */
+    public function getTags(): array;
+
+    /**
+     * @param string $tag
+     * @return bool
+     */
+    public function hasTag(string $tag): bool;
+
+    /**
+     * @return bool
+     */
+    public function isShared(): bool;
+
+    /**
+     * @return mixed
+     */
+    public function resolve(): mixed;
+
+    /**
+     * @return mixed
+     */
+    public function resolveNew(): mixed;
+
+    /**
+     * @param string $id
+     * @return $this
+     */
+    public function setAlias(string $id): DefinitionInterface;
+
+    /**
+     * @param mixed $concrete
+     * @return $this
+     */
+    public function setConcrete(mixed $concrete): DefinitionInterface;
+
+    /**
+     * @param bool $shared
+     * @return $this
+     */
+    public function setShared(bool $shared): DefinitionInterface;
+}
diff --git a/src/Container/DefinitionContainerInterface.php b/src/Container/DefinitionContainerInterface.php
new file mode 100644
index 00000000000..3600e9b76c4
--- /dev/null
+++ b/src/Container/DefinitionContainerInterface.php
@@ -0,0 +1,75 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container;
+
+use Cake\Container\Definition\DefinitionInterface;
+use Cake\Container\Inflector\InflectorInterface;
+use Cake\Container\ServiceProvider\ServiceProviderInterface;
+use Psr\Container\ContainerInterface;
+
+interface DefinitionContainerInterface extends ContainerInterface
+{
+    /**
+     * @param string $id
+     * @param mixed $concrete
+     * @return \Cake\Container\Definition\DefinitionInterface
+     */
+    public function add(string $id, mixed $concrete = null): DefinitionInterface;
+
+    /**
+     * Add multiple definitions at once.
+     *
+     * Supports multiple formats:
+     * - `[Foo::class]` - class name as value, registers as itself
+     * - `['alias' => Foo::class]` - alias as key, class as value
+     * - `[Foo::class => [Bar::class]]` - class with constructor arguments
+     *
+     * @param array<int|string, array<class-string>|class-string> $definitions
+     * @return self
+     */
+    public function addDefinitions(array $definitions): self;
+
+    /**
+     * @param \Cake\Container\ServiceProvider\ServiceProviderInterface $provider
+     * @return self
+     */
+    public function addServiceProvider(ServiceProviderInterface $provider): self;
+
+    /**
+     * @param string $id
+     * @param mixed $concrete
+     * @return \Cake\Container\Definition\DefinitionInterface
+     */
+    public function addShared(string $id, mixed $concrete = null): DefinitionInterface;
+
+    /**
+     * @param string $id
+     * @return \Cake\Container\Definition\DefinitionInterface
+     */
+    public function extend(string $id): DefinitionInterface;
+
+    /**
+     * @param mixed $id
+     * @return mixed
+     */
+    public function getNew(mixed $id): mixed;
+
+    /**
+     * Check if the container has a registered definition for the given id.
+     *
+     * Unlike `has()`, this only checks explicit definitions, not service providers
+     * or delegate containers.
+     *
+     * @param string $id
+     * @return bool
+     */
+    public function hasDefinition(string $id): bool;
+
+    /**
+     * @param string $type
+     * @param callable|null $callback
+     * @return \Cake\Container\Inflector\InflectorInterface
+     */
+    public function inflector(string $type, ?callable $callback = null): InflectorInterface;
+}
diff --git a/src/Container/Exception/ContainerException.php b/src/Container/Exception/ContainerException.php
new file mode 100644
index 00000000000..3dc2c3200c5
--- /dev/null
+++ b/src/Container/Exception/ContainerException.php
@@ -0,0 +1,11 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Exception;
+
+use Psr\Container\ContainerExceptionInterface;
+use RuntimeException;
+
+class ContainerException extends RuntimeException implements ContainerExceptionInterface
+{
+}
diff --git a/src/Container/Exception/NotFoundException.php b/src/Container/Exception/NotFoundException.php
new file mode 100644
index 00000000000..8f857edd74d
--- /dev/null
+++ b/src/Container/Exception/NotFoundException.php
@@ -0,0 +1,11 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Exception;
+
+use InvalidArgumentException;
+use Psr\Container\NotFoundExceptionInterface;
+
+class NotFoundException extends InvalidArgumentException implements NotFoundExceptionInterface
+{
+}
diff --git a/src/Container/Inflector/Inflector.php b/src/Container/Inflector/Inflector.php
new file mode 100644
index 00000000000..9250aab3ec5
--- /dev/null
+++ b/src/Container/Inflector/Inflector.php
@@ -0,0 +1,121 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Inflector;
+
+use Cake\Container\Argument\ArgumentResolverInterface;
+use Cake\Container\Argument\ArgumentResolverTrait;
+use Cake\Container\ContainerAwareTrait;
+
+class Inflector implements ArgumentResolverInterface, InflectorInterface
+{
+    use ArgumentResolverTrait;
+    use ContainerAwareTrait;
+
+    /**
+     * @var string
+     */
+    protected string $type;
+
+    /**
+     * @var callable|null
+     */
+    protected $callback;
+
+    /**
+     * @var array
+     */
+    protected array $methods = [];
+
+    /**
+     * @var array
+     */
+    protected array $properties = [];
+
+    /**
+     * @param string $type
+     * @param callable|null $callback
+     */
+    public function __construct(string $type, ?callable $callback = null)
+    {
+        $this->type = $type;
+        $this->callback = $callback;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getType(): string
+    {
+        return $this->type;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function invokeMethod(string $name, array $args): InflectorInterface
+    {
+        $this->methods[$name] = $args;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function invokeMethods(array $methods): InflectorInterface
+    {
+        foreach ($methods as $name => $args) {
+            $this->invokeMethod($name, $args);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setProperty(string $property, $value): InflectorInterface
+    {
+        $this->properties[$property] = $this->resolveArguments([$value])[0];
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setProperties(array $properties): InflectorInterface
+    {
+        foreach ($properties as $property => $value) {
+            $this->setProperty($property, $value);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function inflect(object $object): void
+    {
+        $properties = $this->resolveArguments(array_values($this->properties));
+        $properties = array_combine(array_keys($this->properties), $properties);
+
+        // array_combine() can technically return false
+        foreach ($properties ?: [] as $property => $value) {
+            $object->{$property} = $value;
+        }
+
+        foreach ($this->methods as $method => $args) {
+            $args = $this->resolveArguments($args);
+            /** @var callable $callable */
+            $callable = [$object, $method];
+            call_user_func_array($callable, $args);
+        }
+
+        if ($this->callback !== null) {
+            call_user_func($this->callback, $object);
+        }
+    }
+}
diff --git a/src/Container/Inflector/InflectorAggregate.php b/src/Container/Inflector/InflectorAggregate.php
new file mode 100644
index 00000000000..118973dd162
--- /dev/null
+++ b/src/Container/Inflector/InflectorAggregate.php
@@ -0,0 +1,53 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Inflector;
+
+use Cake\Container\ContainerAwareTrait;
+use Generator;
+
+class InflectorAggregate implements InflectorAggregateInterface
+{
+    use ContainerAwareTrait;
+
+    /**
+     * @var array<\Cake\Container\Inflector\Inflector>
+     */
+    protected array $inflectors = [];
+
+    /**
+     * @inheritDoc
+     */
+    public function add(string $type, ?callable $callback = null): Inflector
+    {
+        $inflector = new Inflector($type, $callback);
+        $this->inflectors[] = $inflector;
+
+        return $inflector;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function inflect($object): mixed
+    {
+        foreach ($this->getIterator() as $inflector) {
+            $type = $inflector->getType();
+
+            if ($object instanceof $type) {
+                $inflector->setContainer($this->getContainer());
+                $inflector->inflect($object);
+            }
+        }
+
+        return $object;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getIterator(): Generator
+    {
+        yield from $this->inflectors;
+    }
+}
diff --git a/src/Container/Inflector/InflectorAggregateInterface.php b/src/Container/Inflector/InflectorAggregateInterface.php
new file mode 100644
index 00000000000..f80d97b641a
--- /dev/null
+++ b/src/Container/Inflector/InflectorAggregateInterface.php
@@ -0,0 +1,26 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Inflector;
+
+use Cake\Container\ContainerAwareInterface;
+use IteratorAggregate;
+
+/**
+ * @template-extends \IteratorAggregate<string, \Cake\Container\Inflector\Inflector>
+ */
+interface InflectorAggregateInterface extends ContainerAwareInterface, IteratorAggregate
+{
+    /**
+     * @param string $type
+     * @param callable|null $callback
+     * @return \Cake\Container\Inflector\Inflector
+     */
+    public function add(string $type, ?callable $callback = null): Inflector;
+
+    /**
+     * @param object $object
+     * @return mixed
+     */
+    public function inflect(object $object): mixed;
+}
diff --git a/src/Container/Inflector/InflectorInterface.php b/src/Container/Inflector/InflectorInterface.php
new file mode 100644
index 00000000000..c954e72a64e
--- /dev/null
+++ b/src/Container/Inflector/InflectorInterface.php
@@ -0,0 +1,44 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\Inflector;
+
+interface InflectorInterface
+{
+    /**
+     * @return string
+     */
+    public function getType(): string;
+
+    /**
+     * @param object $object
+     * @return void
+     */
+    public function inflect(object $object): void;
+
+    /**
+     * @param string $name
+     * @param array $args
+     * @return $this
+     */
+    public function invokeMethod(string $name, array $args): InflectorInterface;
+
+    /**
+     * @param array $methods
+     * @return $this
+     */
+    public function invokeMethods(array $methods): InflectorInterface;
+
+    /**
+     * @param array $properties
+     * @return $this
+     */
+    public function setProperties(array $properties): InflectorInterface;
+
+    /**
+     * @param string $property
+     * @param mixed $value
+     * @return $this
+     */
+    public function setProperty(string $property, mixed $value): InflectorInterface;
+}
diff --git a/src/Container/LICENSE.txt b/src/Container/LICENSE.txt
new file mode 100644
index 00000000000..38964cd9431
--- /dev/null
+++ b/src/Container/LICENSE.txt
@@ -0,0 +1,21 @@
+# The MIT License (MIT)
+
+Copyright (c) 2021 Phil Bennett <philipobenito@gmail.com>
+
+> Permission is hereby granted, free of charge, to any person obtaining a copy
+> of this software and associated documentation files (the "Software"), to deal
+> in the Software without restriction, including without limitation the rights
+> to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+> copies of the Software, and to permit persons to whom the Software is
+> furnished to do so, subject to the following conditions:
+>
+> The above copyright notice and this permission notice shall be included in
+> all copies or substantial portions of the Software.
+>
+> THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+> IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+> FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+> AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+> LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+> OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+> THE SOFTWARE.
diff --git a/src/Container/README.md b/src/Container/README.md
new file mode 100644
index 00000000000..bfa58fb91ea
--- /dev/null
+++ b/src/Container/README.md
@@ -0,0 +1,19 @@
+# CakePHP Container Library
+
+TBD
+
+# Installation
+
+```
+composer require cakephp/container
+```
+
+# Getting Started
+
+TBD
+
+## Credits
+
+- [Phil Bennett](https://github.com/philipobenito)
+- [thephpleague/container](https://github.com/thephpleague/container)
+- `Orno\Di` contributors
diff --git a/src/Container/ReflectionContainer.php b/src/Container/ReflectionContainer.php
new file mode 100644
index 00000000000..864b621acd3
--- /dev/null
+++ b/src/Container/ReflectionContainer.php
@@ -0,0 +1,164 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container;
+
+use Cake\Container\Argument\ArgumentResolverInterface;
+use Cake\Container\Argument\ArgumentResolverTrait;
+use Cake\Container\Exception\ContainerException;
+use Cake\Container\Exception\NotFoundException;
+use Psr\Container\ContainerInterface;
+use ReflectionClass;
+use ReflectionFunction;
+use ReflectionMethod;
+
+class ReflectionContainer implements ArgumentResolverInterface, ContainerInterface
+{
+    use ArgumentResolverTrait;
+    use ContainerAwareTrait;
+
+    /**
+     * @var bool
+     */
+    protected bool $cacheResolutions;
+
+    /**
+     * @var array
+     */
+    protected array $cache = [];
+
+    /**
+     * @param bool $cacheResolutions
+     */
+    public function __construct(bool $cacheResolutions = false)
+    {
+        $this->cacheResolutions = $cacheResolutions;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function get(string $id, array $args = [])
+    {
+        // Only use cache when no custom args are provided
+        if ($this->cacheResolutions && $args === [] && array_key_exists($id, $this->cache)) {
+            return $this->cache[$id];
+        }
+
+        if (!$this->has($id)) {
+            throw new NotFoundException(
+                sprintf('Alias (%s) is not an existing class and therefore cannot be resolved', $id),
+            );
+        }
+
+        /** @var class-string $id */
+        $reflector = new ReflectionClass($id);
+        $construct = $reflector->getConstructor();
+
+        if ($construct && !$construct->isPublic()) {
+            throw new NotFoundException(
+                sprintf('Alias (%s) has a non-public constructor and therefore cannot be instantiated', $id),
+            );
+        }
+
+        $resolution = $construct === null
+            ? new $id()
+            : $reflector->newInstanceArgs($this->reflectArguments($construct, $args));
+
+        // Only cache when no custom args are provided
+        if ($this->cacheResolutions && $args === []) {
+            $this->cache[$id] = $resolution;
+        }
+
+        return $resolution;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function has($id): bool
+    {
+        return class_exists($id);
+    }
+
+    /**
+     * Get a new instance, bypassing the cache.
+     *
+     * @param string $id
+     * @param array<string, mixed> $args
+     * @return mixed
+     */
+    public function getNew(string $id, array $args = []): mixed
+    {
+        if (!$this->has($id)) {
+            throw new NotFoundException(
+                sprintf('Alias (%s) is not an existing class and therefore cannot be resolved', $id),
+            );
+        }
+
+        /** @var class-string $id */
+        $reflector = new ReflectionClass($id);
+        $construct = $reflector->getConstructor();
+
+        if ($construct && !$construct->isPublic()) {
+            throw new NotFoundException(
+                sprintf('Alias (%s) has a non-public constructor and therefore cannot be instantiated', $id),
+            );
+        }
+
+        return $construct === null
+            ? new $id()
+            : $reflector->newInstanceArgs($this->reflectArguments($construct, $args));
+    }
+
+    /**
+     * @param callable|string $callable
+     * @param array $args
+     * @return mixed
+     * @throws \Psr\Container\ContainerExceptionInterface
+     * @throws \Psr\Container\NotFoundExceptionInterface
+     * @throws \ReflectionException
+     */
+    public function call(callable|string $callable, array $args = []): mixed
+    {
+        if (is_string($callable) && str_contains($callable, '::')) {
+            $callable = explode('::', $callable);
+        }
+
+        if (is_array($callable)) {
+            if (is_string($callable[0])) {
+                // if we have a definition container, try that first, otherwise, reflect
+                try {
+                    $callable[0] = $this->getContainer()->get($callable[0]);
+                } catch (ContainerException) {
+                    $callable[0] = $this->get($callable[0]);
+                }
+            }
+
+            $reflection = new ReflectionMethod($callable[0], $callable[1]);
+
+            if ($reflection->isStatic()) {
+                $callable[0] = null;
+            }
+
+            return $reflection->invokeArgs($callable[0], $this->reflectArguments($reflection, $args));
+        }
+
+        if (is_object($callable)) {
+            $reflection = new ReflectionMethod($callable, '__invoke');
+
+            return $reflection->invokeArgs($callable, $this->reflectArguments($reflection, $args));
+        }
+
+        if (is_callable($callable)) {
+            $reflection = new ReflectionFunction($callable(...));
+
+            return $reflection->invokeArgs($this->reflectArguments($reflection, $args));
+        }
+
+        throw new NotFoundException(sprintf(
+            'Callable (%s) is not a valid callable',
+            $callable,
+        ));
+    }
+}
diff --git a/src/Container/ServiceProvider/AbstractServiceProvider.php b/src/Container/ServiceProvider/AbstractServiceProvider.php
new file mode 100644
index 00000000000..3afb809fdb4
--- /dev/null
+++ b/src/Container/ServiceProvider/AbstractServiceProvider.php
@@ -0,0 +1,34 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\ServiceProvider;
+
+use Cake\Container\ContainerAwareTrait;
+
+abstract class AbstractServiceProvider implements ServiceProviderInterface
+{
+    use ContainerAwareTrait;
+
+    /**
+     * @var string|null
+     */
+    protected ?string $identifier = null;
+
+    /**
+     * @inheritDoc
+     */
+    public function getIdentifier(): string
+    {
+        return $this->identifier ?? static::class;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setIdentifier(string $id): ServiceProviderInterface
+    {
+        $this->identifier = $id;
+
+        return $this;
+    }
+}
diff --git a/src/Container/ServiceProvider/BootableServiceProviderInterface.php b/src/Container/ServiceProvider/BootableServiceProviderInterface.php
new file mode 100644
index 00000000000..7c8e71936a1
--- /dev/null
+++ b/src/Container/ServiceProvider/BootableServiceProviderInterface.php
@@ -0,0 +1,15 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\ServiceProvider;
+
+interface BootableServiceProviderInterface extends ServiceProviderInterface
+{
+    /**
+     * Method will be invoked on registration of a service provider implementing
+     * this interface. Provides ability for eager loading of Service Providers.
+     *
+     * @return void
+     */
+    public function boot(): void;
+}
diff --git a/src/Container/ServiceProvider/ServiceProviderAggregate.php b/src/Container/ServiceProvider/ServiceProviderAggregate.php
new file mode 100644
index 00000000000..f6b298caef3
--- /dev/null
+++ b/src/Container/ServiceProvider/ServiceProviderAggregate.php
@@ -0,0 +1,88 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\ServiceProvider;
+
+use Cake\Container\ContainerAwareTrait;
+use Cake\Container\Exception\ContainerException;
+use Generator;
+
+class ServiceProviderAggregate implements ServiceProviderAggregateInterface
+{
+    use ContainerAwareTrait;
+
+    /**
+     * @var array<\Cake\Container\ServiceProvider\ServiceProviderInterface>
+     */
+    protected array $providers = [];
+
+    /**
+     * @var array
+     */
+    protected array $registered = [];
+
+    /**
+     * @inheritDoc
+     */
+    public function add(ServiceProviderInterface $provider): ServiceProviderAggregateInterface
+    {
+        if (in_array($provider, $this->providers, true)) {
+            return $this;
+        }
+
+        $provider->setContainer($this->getContainer());
+
+        if ($provider instanceof BootableServiceProviderInterface) {
+            $provider->boot();
+        }
+
+        $this->providers[] = $provider;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function provides(string $id): bool
+    {
+        foreach ($this->getIterator() as $provider) {
+            if ($provider->provides($id)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getIterator(): Generator
+    {
+        yield from $this->providers;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function register(string $service): void
+    {
+        if ($this->provides($service) === false) {
+            throw new ContainerException(
+                sprintf('(%s) is not provided by a service provider', $service),
+            );
+        }
+
+        foreach ($this->getIterator() as $provider) {
+            if (in_array($provider->getIdentifier(), $this->registered, true)) {
+                continue;
+            }
+
+            if ($provider->provides($service)) {
+                $provider->register();
+                $this->registered[] = $provider->getIdentifier();
+            }
+        }
+    }
+}
diff --git a/src/Container/ServiceProvider/ServiceProviderAggregateInterface.php b/src/Container/ServiceProvider/ServiceProviderAggregateInterface.php
new file mode 100644
index 00000000000..d4bdcfb8adc
--- /dev/null
+++ b/src/Container/ServiceProvider/ServiceProviderAggregateInterface.php
@@ -0,0 +1,31 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\ServiceProvider;
+
+use Cake\Container\ContainerAwareInterface;
+use IteratorAggregate;
+
+/**
+ * @template-extends \IteratorAggregate<string, \Cake\Container\ServiceProvider\ServiceProviderInterface>
+ */
+interface ServiceProviderAggregateInterface extends ContainerAwareInterface, IteratorAggregate
+{
+    /**
+     * @param \Cake\Container\ServiceProvider\ServiceProviderInterface $provider
+     * @return $this
+     */
+    public function add(ServiceProviderInterface $provider): ServiceProviderAggregateInterface;
+
+    /**
+     * @param string $id
+     * @return bool
+     */
+    public function provides(string $id): bool;
+
+    /**
+     * @param string $service
+     * @return void
+     */
+    public function register(string $service): void;
+}
diff --git a/src/Container/ServiceProvider/ServiceProviderInterface.php b/src/Container/ServiceProvider/ServiceProviderInterface.php
new file mode 100644
index 00000000000..39dd8fe276f
--- /dev/null
+++ b/src/Container/ServiceProvider/ServiceProviderInterface.php
@@ -0,0 +1,31 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Container\ServiceProvider;
+
+use Cake\Container\ContainerAwareInterface;
+
+interface ServiceProviderInterface extends ContainerAwareInterface
+{
+    /**
+     * @return string
+     */
+    public function getIdentifier(): string;
+
+    /**
+     * @param string $id
+     * @return bool
+     */
+    public function provides(string $id): bool;
+
+    /**
+     * @return void
+     */
+    public function register(): void;
+
+    /**
+     * @param string $id
+     * @return $this
+     */
+    public function setIdentifier(string $id): ServiceProviderInterface;
+}
diff --git a/src/Container/composer.json b/src/Container/composer.json
new file mode 100644
index 00000000000..91465f3c610
--- /dev/null
+++ b/src/Container/composer.json
@@ -0,0 +1,45 @@
+{
+    "name": "cakephp/container",
+    "description": "A fast and intuitive dependency injection container.",
+    "type": "library",
+    "keywords": [
+        "cakephp",
+        "container",
+        "dependency",
+        "injection",
+        "di",
+        "service",
+        "provider"
+    ],
+    "homepage": "https://cakephp.org",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Phil Bennett",
+            "email": "mail@philbennett.co.uk",
+            "role": "Developer"
+        },
+        {
+            "name": "CakePHP Community",
+            "homepage": "https://github.com/cakephp/cakephp/graphs/contributors"
+        }
+    ],
+    "support": {
+        "issues": "https://github.com/cakephp/cakephp/issues",
+        "forum": "https://stackoverflow.com/tags/cakephp",
+        "irc": "irc://irc.freenode.org/cakephp",
+        "source": "https://github.com/cakephp/container"
+    },
+    "require": {
+        "php": ">=8.2",
+        "psr/container": "^1.1 || ^2.0"
+    },
+    "provide": {
+        "psr/container-implementation": "^1.0"
+    },
+    "autoload": {
+        "psr-4": {
+            "Cake\\Container\\": "."
+        }
+    }
+}
diff --git a/src/Controller/Attribute/Enum/RequestToDtoSource.php b/src/Controller/Attribute/Enum/RequestToDtoSource.php
new file mode 100644
index 00000000000..4dc8293ec81
--- /dev/null
+++ b/src/Controller/Attribute/Enum/RequestToDtoSource.php
@@ -0,0 +1,15 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Controller\Attribute\Enum;
+
+/**
+ * Source for DTO data mapping.
+ */
+enum RequestToDtoSource: string
+{
+    case Body = 'body';
+    case Query = 'query';
+    case Request = 'request';
+    case Auto = 'auto';
+}
diff --git a/src/Controller/Attribute/ParameterAttributeInterface.php b/src/Controller/Attribute/ParameterAttributeInterface.php
new file mode 100644
index 00000000000..8e17ce6da6f
--- /dev/null
+++ b/src/Controller/Attribute/ParameterAttributeInterface.php
@@ -0,0 +1,25 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Controller\Attribute;
+
+use Cake\Http\ServerRequest;
+use ReflectionParameter;
+
+/**
+ * Interface for controller action parameter attributes.
+ *
+ * Attributes implementing this interface can resolve parameter values
+ * from the request, enabling custom parameter injection in controller actions.
+ */
+interface ParameterAttributeInterface
+{
+    /**
+     * Resolve the parameter value from the request.
+     *
+     * @param \ReflectionParameter $parameter The parameter being resolved
+     * @param \Cake\Http\ServerRequest $request The server request
+     * @return mixed The resolved value
+     */
+    public function resolve(ReflectionParameter $parameter, ServerRequest $request): mixed;
+}
diff --git a/src/Controller/Attribute/RequestToDto.php b/src/Controller/Attribute/RequestToDto.php
new file mode 100644
index 00000000000..fa64719d314
--- /dev/null
+++ b/src/Controller/Attribute/RequestToDto.php
@@ -0,0 +1,97 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Controller\Attribute;
+
+use Attribute;
+use Cake\Controller\Attribute\Enum\RequestToDtoSource;
+use Cake\Controller\Exception\InvalidParameterException;
+use Cake\Http\ServerRequest;
+use ReflectionNamedType;
+use ReflectionParameter;
+
+#[Attribute(Attribute::TARGET_PARAMETER)]
+readonly class RequestToDto implements ParameterAttributeInterface
+{
+    /**
+     * @param string|null $class DTO class name (optional for typed parameters)
+     * @param \Cake\Controller\Attribute\Enum\RequestToDtoSource $source Data source: body, query, request, or auto
+     */
+    public function __construct(
+        protected ?string $class = null,
+        protected RequestToDtoSource $source = RequestToDtoSource::Auto,
+    ) {
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolve(ReflectionParameter $parameter, ServerRequest $request): object
+    {
+        $dtoClass = $this->class;
+        if ($dtoClass === null) {
+            $type = $parameter->getType();
+            if ($type instanceof ReflectionNamedType && !$type->isBuiltin()) {
+                $dtoClass = $type->getName();
+            }
+        }
+
+        if ($dtoClass === null || !class_exists($dtoClass)) {
+            throw new InvalidParameterException([
+                'template' => 'missing_dependency',
+                'parameter' => $parameter->getName(),
+                'type' => $dtoClass ?? 'Dto',
+            ]);
+        }
+
+        if (!method_exists($dtoClass, 'createFromArray')) {
+            throw new InvalidParameterException([
+                'template' => 'missing_dependency',
+                'parameter' => $parameter->getName(),
+                'type' => $dtoClass,
+            ]);
+        }
+
+        /** @var class-string $dtoClass */
+        return $dtoClass::createFromArray($this->extractData($request));
+    }
+
+    /**
+     * Extract data from request based on source.
+     *
+     * @param \Cake\Http\ServerRequest $request The server request
+     * @return array<string, mixed>
+     */
+    protected function extractData(ServerRequest $request): array
+    {
+        return match ($this->source) {
+            RequestToDtoSource::Body => (array)$request->getData(),
+            RequestToDtoSource::Query => $request->getQueryParams(),
+            RequestToDtoSource::Request => array_merge(
+                $request->getQueryParams(),
+                (array)$request->getData(),
+            ),
+            RequestToDtoSource::Auto => $this->extractAutoData($request),
+        };
+    }
+
+    /**
+     * Auto-detect data source based on request method.
+     *
+     * @param \Cake\Http\ServerRequest $request The server request
+     * @return array<string, mixed>
+     */
+    protected function extractAutoData(ServerRequest $request): array
+    {
+        if ($request->is(['get', 'head'])) {
+            return $request->getQueryParams();
+        }
+
+        $data = (array)$request->getData();
+        if ($data !== []) {
+            return $data;
+        }
+
+        return $request->getQueryParams();
+    }
+}
diff --git a/src/Controller/Component/FormProtectionComponent.php b/src/Controller/Component/FormProtectionComponent.php
index 924fbe87acf..f57d7ed7990 100644
--- a/src/Controller/Component/FormProtectionComponent.php
+++ b/src/Controller/Component/FormProtectionComponent.php
@@ -142,6 +142,33 @@ public function implementedEvents(): array
         ];
     }
 
+    /**
+     * Unlock actions from validation.
+     *
+     * @param string|array<string> $actions Action or list of actions to unlock.
+     * @param bool $merge Whether to merge with existing unlocked actions or replace them.
+     * @return $this
+     */
+    public function unlockActions(string|array $actions, bool $merge = true)
+    {
+        return $this->setConfig('unlockedActions', (array)$actions, $merge);
+    }
+
+    /**
+     * Unlock fields from validation.
+     *
+     * Dot notation can be used to unlock nested fields. For example, `user.name`
+     * will unlock the `name` field in the `user` array.
+     *
+     * @param string|array<string> $fields Field or list of fields to unlock.
+     * @param bool $merge Whether to merge with existing unlocked fields or replace them.
+     * @return $this
+     */
+    public function unlockFields(string|array $fields, bool $merge = true)
+    {
+        return $this->setConfig('unlockedFields', (array)$fields, $merge);
+    }
+
     /**
      * Throws a 400 - Bad request exception or calls custom callback.
      *
diff --git a/src/Controller/ComponentRegistry.php b/src/Controller/ComponentRegistry.php
index 0e49f576ac8..db7e1a236c1 100644
--- a/src/Controller/ComponentRegistry.php
+++ b/src/Controller/ComponentRegistry.php
@@ -27,8 +27,8 @@
 use League\Container\Argument\ArgumentResolverTrait;
 use League\Container\Argument\LiteralArgument;
 use League\Container\Argument\ResolvableArgument;
-use League\Container\Exception\NotFoundException;
 use League\Container\ReflectionContainer;
+use Psr\Container\NotFoundExceptionInterface;
 use ReflectionClass;
 use ReflectionFunctionAbstract;
 use ReflectionMethod;
@@ -180,7 +180,7 @@ protected function _create(object|string $class, string $alias, array $config):
             try {
                 $this->container->extend($class);
                 $hasDefinition = true;
-            } catch (NotFoundException) {
+            } catch (NotFoundExceptionInterface) {
                 // No definition exists yet
             }
 
diff --git a/src/Controller/Controller.php b/src/Controller/Controller.php
index 1518729161c..8646c0d2a88 100644
--- a/src/Controller/Controller.php
+++ b/src/Controller/Controller.php
@@ -47,6 +47,7 @@
 use ReflectionMethod;
 use function Cake\Core\namespaceSplit;
 use function Cake\Core\pluginSplit;
+use function Cake\Core\triggerWarning;
 
 /**
  * Application controller class for organization of business logic.
@@ -282,6 +283,28 @@ public function components(): ComponentRegistry
      */
     public function loadComponent(string $name, array $config = []): Component
     {
+        [, $alias] = pluginSplit($name);
+
+        if ($this->defaultTable) {
+            if (str_contains($this->defaultTable, '\\')) {
+                $tableAlias = App::shortName($this->defaultTable, 'Model/Table', 'Table');
+            } else {
+                [, $tableAlias] = pluginSplit($this->defaultTable, true);
+            }
+
+            if ($alias === $tableAlias) {
+                triggerWarning(sprintf(
+                    'Component alias `%s` clashes with the default table name `%s`. ' .
+                    'The table name will take precedence when accessing `$this->%s`. ' .
+                    'Consider using a different component alias or set `Controller::$defaultTable` to ' .
+                    "an empty string if the controller doesn't use a table.",
+                    $alias,
+                    $this->defaultTable,
+                    $alias,
+                ));
+            }
+        }
+
         return $this->components()->load($name, $config);
     }
 
diff --git a/src/Controller/ControllerFactory.php b/src/Controller/ControllerFactory.php
index 486f25112e1..9b4079287ce 100644
--- a/src/Controller/ControllerFactory.php
+++ b/src/Controller/ControllerFactory.php
@@ -16,6 +16,7 @@
  */
 namespace Cake\Controller;
 
+use Cake\Controller\Attribute\ParameterAttributeInterface;
 use Cake\Controller\Exception\InvalidParameterException;
 use Cake\Core\App;
 use Cake\Core\ContainerInterface;
@@ -31,6 +32,7 @@
 use ReflectionClass;
 use ReflectionFunction;
 use ReflectionNamedType;
+use ReflectionParameter;
 use function Cake\Core\toBool;
 use function Cake\Core\toFloat;
 use function Cake\Core\toInt;
@@ -184,7 +186,14 @@ protected function getActionArgs(Closure $action, array $passedParams): array
     {
         $resolved = [];
         $function = new ReflectionFunction($action);
+        $request = $this->controller->getRequest();
         foreach ($function->getParameters() as $parameter) {
+            $attributeValue = $this->resolveParameterAttribute($parameter, $request);
+            if ($attributeValue !== null) {
+                $resolved[] = $attributeValue;
+                continue;
+            }
+
             $type = $parameter->getType();
 
             // Check for dependency injection for classes
@@ -269,6 +278,25 @@ protected function getActionArgs(Closure $action, array $passedParams): array
         return array_merge($resolved, $passedParams);
     }
 
+    /**
+     * Resolve parameter value from attributes implementing ParameterAttributeInterface.
+     *
+     * @param \ReflectionParameter $parameter The parameter to resolve
+     * @param \Cake\Http\ServerRequest $request The server request
+     * @return mixed The resolved value or null if no matching attribute found
+     */
+    protected function resolveParameterAttribute(ReflectionParameter $parameter, ServerRequest $request): mixed
+    {
+        foreach ($parameter->getAttributes() as $attribute) {
+            $instance = $attribute->newInstance();
+            if ($instance instanceof ParameterAttributeInterface) {
+                return $instance->resolve($parameter, $request);
+            }
+        }
+
+        return null;
+    }
+
     /**
      * Coerces string argument to primitive type.
      *
diff --git a/src/Core/Attribute/Configure.php b/src/Core/Attribute/Configure.php
index 92d9e4e7d21..4bd35b9a205 100644
--- a/src/Core/Attribute/Configure.php
+++ b/src/Core/Attribute/Configure.php
@@ -42,12 +42,12 @@
  * ```
  */
 #[Attribute(Attribute::TARGET_PARAMETER)]
-class Configure implements AttributeInterface
+readonly class Configure implements AttributeInterface
 {
     /**
      * @param string $name
      */
-    public function __construct(private string $name)
+    public function __construct(protected string $name)
     {
     }
 
diff --git a/src/Core/CakeContainerBridge.php b/src/Core/CakeContainerBridge.php
new file mode 100644
index 00000000000..ec2e9acae7a
--- /dev/null
+++ b/src/Core/CakeContainerBridge.php
@@ -0,0 +1,132 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Core;
+
+use Cake\Container\Container as CakeContainer;
+use Cake\Container\ServiceProvider\ServiceProviderInterface as CakeServiceProviderInterface;
+use InvalidArgumentException;
+use League\Container\Definition\DefinitionInterface;
+use League\Container\Inflector\InflectorInterface;
+use League\Container\ServiceProvider\ServiceProviderInterface;
+use Psr\Container\ContainerInterface as PsrContainerInterface;
+
+/**
+ * Bridge class that wraps CakePHP's built-in container to satisfy ContainerInterface.
+ *
+ * This minimal bridge enables using the CakePHP container while maintaining
+ * backwards compatibility with code expecting ContainerInterface.
+ */
+class CakeContainerBridge implements ContainerInterface
+{
+    /**
+     * @param \Cake\Container\Container $container The wrapped CakePHP container
+     */
+    public function __construct(
+        protected CakeContainer $container,
+    ) {
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function add(string $id, mixed $concrete = null, bool $overwrite = false): DefinitionInterface
+    {
+        $definition = $this->container->add($id, $concrete);
+
+        return new CakeDefinitionBridge($definition, $this);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addServiceProvider(ServiceProviderInterface $provider): static
+    {
+        if (!$provider instanceof CakeServiceProviderInterface) {
+            throw new InvalidArgumentException(sprintf(
+                'Service provider must implement `%s` when using the CakePHP container',
+                CakeServiceProviderInterface::class,
+            ));
+        }
+        $this->container->addServiceProvider($provider);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addShared(string $id, mixed $concrete = null, bool $overwrite = false): DefinitionInterface
+    {
+        $definition = $this->container->addShared($id, $concrete);
+
+        return new CakeDefinitionBridge($definition, $this);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function extend(string $id): DefinitionInterface
+    {
+        $definition = $this->container->extend($id);
+
+        return new CakeDefinitionBridge($definition, $this);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getNew(string $id): mixed
+    {
+        return $this->container->getNew($id);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function inflector(string $type, ?callable $callback = null): InflectorInterface
+    {
+        $inflector = $this->container->inflector($type, $callback);
+
+        return new CakeInflectorBridge($inflector);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function get(string $id): mixed
+    {
+        return $this->container->get($id);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function has(string $id): bool
+    {
+        return $this->container->has($id);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function delegate(PsrContainerInterface $container): PsrContainerInterface
+    {
+        $this->container->delegate($container);
+
+        return $this;
+    }
+}
diff --git a/src/Core/CakeDefinitionBridge.php b/src/Core/CakeDefinitionBridge.php
new file mode 100644
index 00000000000..24c4aa210b0
--- /dev/null
+++ b/src/Core/CakeDefinitionBridge.php
@@ -0,0 +1,195 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Core;
+
+use Cake\Container\Definition\DefinitionInterface as CakeDefinitionInterface;
+use League\Container\ContainerAwareInterface;
+use League\Container\Definition\DefinitionInterface;
+use League\Container\DefinitionContainerInterface;
+
+/**
+ * Bridge for Definition objects.
+ *
+ * Wraps CakePHP's Definition to satisfy League's DefinitionInterface.
+ *
+ * @internal
+ */
+class CakeDefinitionBridge implements DefinitionInterface
+{
+    /**
+     * @param \Cake\Container\Definition\DefinitionInterface $definition The wrapped definition
+     * @param \League\Container\DefinitionContainerInterface $container The container
+     */
+    public function __construct(
+        protected CakeDefinitionInterface $definition,
+        protected DefinitionContainerInterface $container,
+    ) {
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addArgument(mixed $arg): DefinitionInterface
+    {
+        $this->definition->addArgument($arg);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addArguments(array $args): DefinitionInterface
+    {
+        $this->definition->addArguments($args);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addMethodCall(string $method, array $args = []): DefinitionInterface
+    {
+        $this->definition->addMethodCall($method, $args);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addMethodCalls(array $methods = []): DefinitionInterface
+    {
+        $this->definition->addMethodCalls($methods);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function addTag(string $tag): DefinitionInterface
+    {
+        $this->definition->addTag($tag);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getAlias(): string
+    {
+        return $this->definition->getAlias();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getConcrete(): mixed
+    {
+        return $this->definition->getConcrete();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getTags(): array
+    {
+        return $this->definition->getTags();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function hasTag(string $tag): bool
+    {
+        return $this->definition->hasTag($tag);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function isShared(): bool
+    {
+        return $this->definition->isShared();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolve(): mixed
+    {
+        return $this->definition->resolve();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function resolveNew(): mixed
+    {
+        return $this->definition->resolveNew();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setAlias(string $id): DefinitionInterface
+    {
+        // CakePHP's Definition doesn't have setAlias, but we can return self
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setConcrete(mixed $concrete): DefinitionInterface
+    {
+        $this->definition->setConcrete($concrete);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setShared(bool $shared): DefinitionInterface
+    {
+        $this->definition->setShared($shared);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getContainer(): DefinitionContainerInterface
+    {
+        return $this->container;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setContainer(DefinitionContainerInterface $container): ContainerAwareInterface
+    {
+        $this->container = $container;
+
+        return $this;
+    }
+}
diff --git a/src/Core/CakeInflectorBridge.php b/src/Core/CakeInflectorBridge.php
new file mode 100644
index 00000000000..3b3889a45f7
--- /dev/null
+++ b/src/Core/CakeInflectorBridge.php
@@ -0,0 +1,94 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Core;
+
+use Cake\Container\Inflector\InflectorInterface as CakeInflectorInterface;
+use League\Container\Inflector\InflectorInterface;
+
+/**
+ * Bridge for Inflector objects.
+ *
+ * Wraps CakePHP's Inflector to satisfy League's InflectorInterface.
+ *
+ * @internal
+ */
+class CakeInflectorBridge implements InflectorInterface
+{
+    /**
+     * @param \Cake\Container\Inflector\InflectorInterface $inflector The wrapped inflector
+     */
+    public function __construct(
+        protected CakeInflectorInterface $inflector,
+    ) {
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getType(): string
+    {
+        return $this->inflector->getType();
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function invokeMethod(string $name, array $args): InflectorInterface
+    {
+        $this->inflector->invokeMethod($name, $args);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function invokeMethods(array $methods): InflectorInterface
+    {
+        $this->inflector->invokeMethods($methods);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setProperty(string $property, mixed $value): InflectorInterface
+    {
+        $this->inflector->setProperty($property, $value);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function setProperties(array $properties): InflectorInterface
+    {
+        $this->inflector->setProperties($properties);
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function inflect(object $object): void
+    {
+        $this->inflector->inflect($object);
+    }
+}
diff --git a/src/Core/ConsoleHelpHeaderProviderInterface.php b/src/Core/ConsoleHelpHeaderProviderInterface.php
new file mode 100644
index 00000000000..176a169825d
--- /dev/null
+++ b/src/Core/ConsoleHelpHeaderProviderInterface.php
@@ -0,0 +1,29 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright 2005-2011, Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Core;
+
+/**
+ * Provides a custom header line for console help output.
+ */
+interface ConsoleHelpHeaderProviderInterface
+{
+    /**
+     * Get the header line to render at the top of console help output.
+     *
+     * @return string
+     */
+    public function getConsoleHelpHeader(): string;
+}
diff --git a/src/Core/ContainerFactory.php b/src/Core/ContainerFactory.php
new file mode 100644
index 00000000000..c4bd318b881
--- /dev/null
+++ b/src/Core/ContainerFactory.php
@@ -0,0 +1,46 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Core;
+
+use Cake\Container\Container as CakeContainer;
+
+/**
+ * Factory for creating the appropriate DI container based on configuration.
+ *
+ * The container selection is controlled by `Configure::read('App.container')`:
+ * - 'cake': Uses the built-in CakePHP container (wrapped in CakeContainerBridge)
+ * - Any other value or not set: Uses the League container (default, backwards compatible)
+ *
+ * When using the 'cake' container, applications may need to adjust code that
+ * uses League-specific features. The basic container API (`add`, `addShared`,
+ * `get`, `has`, `addServiceProvider`) works identically in both containers.
+ */
+class ContainerFactory
+{
+    /**
+     * Create a new container instance based on configuration.
+     *
+     * @return \Cake\Core\ContainerInterface
+     */
+    public static function create(): ContainerInterface
+    {
+        return match (Configure::read('App.container')) {
+            'cake' => new CakeContainerBridge(new CakeContainer()),
+            default => new Container(),
+        };
+    }
+}
diff --git a/src/Core/PluginConfig.php b/src/Core/PluginConfig.php
index 5d02c0a82dc..6cfe257928f 100644
--- a/src/Core/PluginConfig.php
+++ b/src/Core/PluginConfig.php
@@ -26,6 +26,13 @@
  */
 class PluginConfig
 {
+    /**
+     * Cache for installed plugins to avoid re-reading files
+     *
+     * @var array<string, array<string, mixed>>|null
+     */
+    private static ?array $cachedPlugins = null;
+
     /**
      * Load the path information stored in vendor/cakephp-plugins.php
      *
@@ -56,13 +63,30 @@ public static function loadInstallerConfig(): void
     }
 
     /**
-     * Get the config how plugins should be loaded
+     * Get an array of all installed plugins and their configuration options.
      *
-     * @param string|null $path The absolute path to the composer.lock file to retrieve the versions from
-     * @return array
+     * Returns an array of plugin configurations with keys:
+     * - bootstrap: Enable bootstrap hook (if isLoaded)
+     * - console: Enable console hook (if isLoaded)
+     * - events: Enable events hook (if isLoaded)
+     * - isLoaded: Whether plugin is configured to load
+     * - isUnknown: Present and set to true when a plugin is configured but not found in the installed plugins list
+     * - middleware: Enable middleware hook (if isLoaded)
+     * - onlyCli: Load only in CLI mode (if isLoaded)
+     * - onlyDebug: Load only in debug mode (if isLoaded)
+     * - optional: Plugin is optional (if isLoaded)
+     * - path: Plugin filesystem path (only present for installed plugins, not for unknown ones)
+     * - routes: Enable routes hook (if isLoaded)
+     * - services: Enable services hook (if isLoaded)
+     *
+     * @return array<string, array<string, mixed>> Plugin name => configuration
      */
-    public static function getAppConfig(?string $path = null): array
+    public static function getInstalledPlugins(): array
     {
+        if (self::$cachedPlugins !== null) {
+            return self::$cachedPlugins;
+        }
+
         self::loadInstallerConfig();
 
         // phpcs:ignore
@@ -73,12 +97,6 @@ public static function getAppConfig(?string $path = null): array
             $pluginLoadConfig = [];
         }
 
-        try {
-            $composerVersions = self::getVersions($path);
-        } catch (CakeException) {
-            $composerVersions = [];
-        }
-
         $result = [];
         $availablePlugins = Configure::read('plugins', []);
         if ($availablePlugins && is_array($availablePlugins)) {
@@ -87,6 +105,7 @@ public static function getAppConfig(?string $path = null): array
                     $options = $pluginLoadConfig[$pluginName];
                     $hooks = PluginInterface::VALID_HOOKS;
                     $mainConfig = [
+                        'path' => $pluginPath,
                         'isLoaded' => true,
                         'onlyDebug' => $options['onlyDebug'] ?? false,
                         'onlyCli' => $options['onlyCli'] ?? false,
@@ -97,24 +116,10 @@ public static function getAppConfig(?string $path = null): array
                     }
                     $result[$pluginName] = $mainConfig;
                 } else {
-                    $result[$pluginName]['isLoaded'] = false;
-                }
-
-                try {
-                    $packageName = self::getPackageNameFromPath($pluginPath);
-                    $result[$pluginName]['packagePath'] = $pluginPath;
-                    $result[$pluginName]['package'] = $packageName;
-                } catch (CakeException) {
-                    $packageName = null;
-                }
-                if ($composerVersions && $packageName) {
-                    if (array_key_exists($packageName, $composerVersions['packages'])) {
-                        $result[$pluginName]['version'] = $composerVersions['packages'][$packageName];
-                        $result[$pluginName]['isDevPackage'] = false;
-                    } elseif (array_key_exists($packageName, $composerVersions['devPackages'])) {
-                        $result[$pluginName]['version'] = $composerVersions['devPackages'][$packageName];
-                        $result[$pluginName]['isDevPackage'] = true;
-                    }
+                    $result[$pluginName] = [
+                        'path' => $pluginPath,
+                        'isLoaded' => false,
+                    ];
                 }
             }
         }
@@ -125,12 +130,74 @@ public static function getAppConfig(?string $path = null): array
             $result[$unknownPlugin]['isUnknown'] = true;
         }
 
+        return self::$cachedPlugins = $result;
+    }
+
+    /**
+     * Clear the cached plugins data. Useful for testing.
+     *
+     * @return void
+     */
+    public static function clearCache(): void
+    {
+        self::$cachedPlugins = null;
+    }
+
+    /**
+     * Get the config how plugins should be loaded with enriched package metadata.
+     *
+     * @param string|null $path The absolute path to the composer.lock file to retrieve the versions from
+     * @return array<string, array<string, mixed>> Plugin name => enriched configuration with package metadata
+     */
+    public static function getAppConfig(?string $path = null): array
+    {
+        // Get base plugin configuration (paths and load config)
+        $result = self::getInstalledPlugins();
+
+        try {
+            $composerVersions = self::getVersions($path);
+        } catch (CakeException) {
+            $composerVersions = [];
+        }
+
+        // Enrich with package metadata and versions
+        foreach ($result as $pluginName => $config) {
+            // Skip unknown plugins (no path available)
+            if (!isset($config['path'])) {
+                continue;
+            }
+
+            try {
+                $packageName = self::getPackageNameFromPath($config['path']);
+                $result[$pluginName]['packagePath'] = $config['path'];
+                $result[$pluginName]['package'] = $packageName;
+            } catch (CakeException) {
+                $packageName = null;
+            }
+
+            if ($composerVersions && $packageName) {
+                foreach (['packages' => false, 'devPackages' => true] as $key => $isDev) {
+                    if (array_key_exists($packageName, $composerVersions[$key])) {
+                        $result[$pluginName]['version'] = $composerVersions[$key][$packageName];
+                        $result[$pluginName]['isDevPackage'] = $isDev;
+                        break;
+                    }
+                }
+            }
+
+            // Remove 'path' key to maintain BC (getAppConfig uses packagePath instead)
+            unset($result[$pluginName]['path']);
+        }
+
         return $result;
     }
 
     /**
+     * Get package versions from composer.lock file.
+     *
      * @param string|null $path The absolute path to the composer.lock file to retrieve the versions from
-     * @return array
+     * @return array{packages: array<string, string>, devPackages: array<string, string>} Array with 'packages' and 'devPackages' keys
+     * @throws \Cake\Core\Exception\CakeException When composer.lock is missing, unreadable, or invalid
      */
     public static function getVersions(?string $path = null): array
     {
@@ -160,8 +227,11 @@ public static function getVersions(?string $path = null): array
     }
 
     /**
-     * @param string $path
-     * @return string
+     * Extract package name from composer.json in the given path.
+     *
+     * @param string $path The plugin path containing composer.json
+     * @return string The package name (e.g., 'cakephp/debug-kit')
+     * @throws \Cake\Core\Exception\CakeException When composer.json is missing, unreadable, or invalid
      */
     protected static function getPackageNameFromPath(string $path): string
     {
diff --git a/src/Core/TestSuite/ContainerStubTrait.php b/src/Core/TestSuite/ContainerStubTrait.php
index b58f7a19b51..5b05ea24efb 100644
--- a/src/Core/TestSuite/ContainerStubTrait.php
+++ b/src/Core/TestSuite/ContainerStubTrait.php
@@ -24,9 +24,9 @@
 use Cake\Event\EventInterface;
 use Cake\Routing\Router;
 use Closure;
-use League\Container\Exception\NotFoundException;
 use LogicException;
 use PHPUnit\Framework\Attributes\After;
+use Psr\Container\NotFoundExceptionInterface;
 
 /**
  * A set of methods used for defining container services
@@ -165,7 +165,7 @@ public function modifyContainer(EventInterface $event, ContainerInterface $conta
             if ($container->has($key)) {
                 try {
                     $container->extend($key)->setConcrete($factory);
-                } catch (NotFoundException) {
+                } catch (NotFoundExceptionInterface) {
                     $container->add($key, $factory);
                 }
             } else {
diff --git a/src/Core/composer.json b/src/Core/composer.json
index 68607d314d9..518b5618769 100644
--- a/src/Core/composer.json
+++ b/src/Core/composer.json
@@ -23,7 +23,7 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/utility": "^5.3.0",
+        "cakephp/utility": "5.4.*@dev",
         "league/container": "^5.1",
         "psr/container": "^1.1 || ^2.0"
     },
diff --git a/src/Database/Connection.php b/src/Database/Connection.php
index 119dfb9b66f..8f859d889b9 100644
--- a/src/Database/Connection.php
+++ b/src/Database/Connection.php
@@ -105,6 +105,13 @@ class Connection implements ConnectionInterface
      */
     protected ?NestedTransactionRollbackException $nestedTransactionRollbackException = null;
 
+    /**
+     * Callbacks to execute after the outermost transaction commits.
+     *
+     * @var array<\Closure>
+     */
+    protected array $afterCommitCallbacks = [];
+
     protected QueryFactory $queryFactory;
 
     /**
@@ -471,6 +478,26 @@ public function begin(): void
         }
     }
 
+    /**
+     * Register a callback to run after the outermost transaction commits.
+     *
+     * If no transaction is active, the callback executes immediately.
+     * Callbacks are discarded on rollback.
+     *
+     * @param \Closure $callback Callback to execute after commit.
+     * @return void
+     */
+    public function afterCommit(Closure $callback): void
+    {
+        if (!$this->_transactionStarted) {
+            $callback();
+
+            return;
+        }
+
+        $this->afterCommitCallbacks[] = $callback;
+    }
+
     /**
      * Commits current transaction.
      *
@@ -494,7 +521,15 @@ public function commit(): bool
             $this->_transactionStarted = false;
             $this->nestedTransactionRollbackException = null;
 
-            return $this->getWriteDriver()->commitTransaction();
+            $result = $this->getWriteDriver()->commitTransaction();
+
+            $callbacks = $this->afterCommitCallbacks;
+            $this->afterCommitCallbacks = [];
+            foreach ($callbacks as $cb) {
+                $cb();
+            }
+
+            return $result;
         }
         if ($this->isSavePointsEnabled()) {
             $this->releaseSavePoint((string)$this->_transactionLevel);
@@ -524,6 +559,7 @@ public function rollback(?bool $toBeginning = null): bool
             $this->_transactionLevel = 0;
             $this->_transactionStarted = false;
             $this->nestedTransactionRollbackException = null;
+            $this->afterCommitCallbacks = [];
             $this->getWriteDriver()->rollbackTransaction();
 
             return true;
diff --git a/src/Database/Driver/Mysql.php b/src/Database/Driver/Mysql.php
index a43e478e8ad..6c3af56cbff 100644
--- a/src/Database/Driver/Mysql.php
+++ b/src/Database/Driver/Mysql.php
@@ -18,6 +18,8 @@
 
 use Cake\Database\Driver;
 use Cake\Database\DriverFeatureEnum;
+use Cake\Database\Expression\DistinctComparisonExpression;
+use Cake\Database\Expression\StringAggExpression;
 use Cake\Database\Query;
 use Cake\Database\Query\SelectQuery;
 use Cake\Database\Schema\MysqlSchemaDialect;
@@ -31,6 +33,55 @@
  */
 class Mysql extends Driver
 {
+    /**
+     * @inheritDoc
+     */
+    protected function _expressionTranslators(): array
+    {
+        return [
+            StringAggExpression::class => 'transformStringAggExpression',
+            DistinctComparisonExpression::class => 'transformDistinctComparisonExpression',
+        ];
+    }
+
+    /**
+     * Translates IS [NOT] DISTINCT FROM into MySQL-specific syntax.
+     *
+     * @param \Cake\Database\Expression\DistinctComparisonExpression $expression The expression to translate.
+     * @return void
+     */
+    protected function transformDistinctComparisonExpression(DistinctComparisonExpression $expression): void
+    {
+        $operator = strtoupper($expression->getOperator());
+        if ($operator === 'IS NOT DISTINCT FROM') {
+            $expression->setOperator('<=>');
+        } elseif ($operator === 'IS DISTINCT FROM') {
+            $expression->setOperator('<=>');
+            $expression->setNot(true);
+        }
+    }
+
+    /**
+     * Translates portable string aggregation to MySQL/MariaDB specific syntax.
+     *
+     * @param \Cake\Database\Expression\StringAggExpression $expression The expression to translate.
+     * @return void
+     */
+    protected function transformStringAggExpression(StringAggExpression $expression): void
+    {
+        if ($this->supports(DriverFeatureEnum::STRING_AGG)) {
+            $expression
+                ->setName('STRING_AGG')
+                ->setSyntax(StringAggExpression::SYNTAX_STANDARD);
+
+            return;
+        }
+
+        $expression
+            ->setName('GROUP_CONCAT')
+            ->setSyntax(StringAggExpression::SYNTAX_GROUP_CONCAT);
+    }
+
     /**
      * @inheritDoc
      */
@@ -102,16 +153,22 @@ class Mysql extends Driver
             'json' => '5.7.0',
             'cte' => '8.0.0',
             'window' => '8.0.0',
+            'string-agg' => '99.0.0',
             'intersect' => '8.0.31',
             'intersect-all' => '8.0.31',
+            'except' => '8.0.31',
+            'except-all' => '8.0.31',
             'check-constraints' => '8.0.16',
         ],
         'mariadb' => [
             'json' => '10.2.7',
             'cte' => '10.2.1',
             'window' => '10.2.0',
+            'string-agg' => '10.5.0',
             'intersect' => '10.3.0',
             'intersect-all' => '10.5.0',
+            'except' => '10.3.0',
+            'except-all' => '10.5.0',
             'check-constraints' => '10.2.1',
         ],
     ];
@@ -255,8 +312,12 @@ public function supports(DriverFeatureEnum $feature): bool
             DriverFeatureEnum::CTE,
             DriverFeatureEnum::JSON,
             DriverFeatureEnum::WINDOW => $versionCompare(),
+            DriverFeatureEnum::STRING_AGG => $versionCompare(),
+            DriverFeatureEnum::GROUP_CONCAT => true,
             DriverFeatureEnum::INTERSECT => $versionCompare(),
             DriverFeatureEnum::INTERSECT_ALL => $versionCompare(),
+            DriverFeatureEnum::EXCEPT => $versionCompare(),
+            DriverFeatureEnum::EXCEPT_ALL => $versionCompare(),
             DriverFeatureEnum::CHECK_CONSTRAINTS => $versionCompare(),
             DriverFeatureEnum::SET_OPERATIONS_ORDER_BY => true,
             DriverFeatureEnum::OPTIMIZER_HINT_COMMENT => true,
diff --git a/src/Database/Driver/Postgres.php b/src/Database/Driver/Postgres.php
index 78574daea08..3795733a1d8 100644
--- a/src/Database/Driver/Postgres.php
+++ b/src/Database/Driver/Postgres.php
@@ -20,6 +20,7 @@
 use Cake\Database\DriverFeatureEnum;
 use Cake\Database\Expression\FunctionExpression;
 use Cake\Database\Expression\IdentifierExpression;
+use Cake\Database\Expression\StringAggExpression;
 use Cake\Database\Expression\StringExpression;
 use Cake\Database\PostgresCompiler;
 use Cake\Database\Query\InsertQuery;
@@ -206,8 +207,12 @@ public function supports(DriverFeatureEnum $feature): bool
             DriverFeatureEnum::SAVEPOINT,
             DriverFeatureEnum::TRUNCATE_WITH_CONSTRAINTS,
             DriverFeatureEnum::WINDOW => true,
+            DriverFeatureEnum::STRING_AGG => true,
+            DriverFeatureEnum::GROUP_CONCAT => false,
             DriverFeatureEnum::INTERSECT => true,
             DriverFeatureEnum::INTERSECT_ALL => true,
+            DriverFeatureEnum::EXCEPT => true,
+            DriverFeatureEnum::EXCEPT_ALL => true,
             DriverFeatureEnum::SET_OPERATIONS_ORDER_BY => true,
             DriverFeatureEnum::DISABLE_CONSTRAINT_WITHOUT_TRANSACTION => false,
             DriverFeatureEnum::OPTIMIZER_HINT_COMMENT => true,
@@ -242,11 +247,26 @@ protected function _expressionTranslators(): array
     {
         return [
             IdentifierExpression::class => '_transformIdentifierExpression',
+            StringAggExpression::class => '_transformStringAggExpression',
             FunctionExpression::class => '_transformFunctionExpression',
             StringExpression::class => '_transformStringExpression',
         ];
     }
 
+    /**
+     * Receives a StringAggExpression and changes it so that it conforms to this
+     * SQL dialect.
+     *
+     * @param \Cake\Database\Expression\StringAggExpression $expression The expression to convert.
+     * @return void
+     */
+    protected function _transformStringAggExpression(StringAggExpression $expression): void
+    {
+        $expression
+            ->setName('STRING_AGG')
+            ->setSyntax(StringAggExpression::SYNTAX_STANDARD);
+    }
+
     /**
      * Changes identifier expression into postgresql format.
      *
diff --git a/src/Database/Driver/Sqlite.php b/src/Database/Driver/Sqlite.php
index 2635dfb139f..56ed75f129e 100644
--- a/src/Database/Driver/Sqlite.php
+++ b/src/Database/Driver/Sqlite.php
@@ -19,6 +19,7 @@
 use Cake\Database\Driver;
 use Cake\Database\DriverFeatureEnum;
 use Cake\Database\Expression\FunctionExpression;
+use Cake\Database\Expression\StringAggExpression;
 use Cake\Database\Expression\TupleComparison;
 use Cake\Database\Schema\SchemaDialect;
 use Cake\Database\Schema\SqliteSchemaDialect;
@@ -101,6 +102,7 @@ class Sqlite extends Driver
      */
     protected array $featureVersions = [
         'cte' => '3.8.3',
+        'string-agg' => '3.44.0',
         'window' => '3.28.0',
     ];
 
@@ -199,13 +201,17 @@ public function supports(DriverFeatureEnum $feature): bool
             DriverFeatureEnum::JSON => false,
 
             DriverFeatureEnum::CTE,
+            DriverFeatureEnum::STRING_AGG,
             DriverFeatureEnum::WINDOW => version_compare(
                 $this->version(),
                 $this->featureVersions[$feature->value],
                 '>=',
             ),
+            DriverFeatureEnum::GROUP_CONCAT => true,
             DriverFeatureEnum::INTERSECT => true,
             DriverFeatureEnum::INTERSECT_ALL => false,
+            DriverFeatureEnum::EXCEPT => true,
+            DriverFeatureEnum::EXCEPT_ALL => false,
             DriverFeatureEnum::SET_OPERATIONS_ORDER_BY => false,
             DriverFeatureEnum::OPTIMIZER_HINT_COMMENT => false,
             DriverFeatureEnum::CHECK_CONSTRAINTS => true,
@@ -226,11 +232,26 @@ public function schemaDialect(): SchemaDialect
     protected function _expressionTranslators(): array
     {
         return [
+            StringAggExpression::class => '_transformStringAggExpression',
             FunctionExpression::class => '_transformFunctionExpression',
             TupleComparison::class => '_transformTupleComparison',
         ];
     }
 
+    /**
+     * Receives a StringAggExpression and changes it so that it conforms to this
+     * SQL dialect.
+     *
+     * @param \Cake\Database\Expression\StringAggExpression $expression The expression to convert.
+     * @return void
+     */
+    protected function _transformStringAggExpression(StringAggExpression $expression): void
+    {
+        $expression
+            ->setName($this->supports(DriverFeatureEnum::STRING_AGG) ? 'STRING_AGG' : 'GROUP_CONCAT')
+            ->setSyntax(StringAggExpression::SYNTAX_STANDARD);
+    }
+
     /**
      * Receives a FunctionExpression and changes it so that it conforms to this
      * SQL dialect.
diff --git a/src/Database/Driver/Sqlserver.php b/src/Database/Driver/Sqlserver.php
index b9d0fb77f01..aa8c48f4b98 100644
--- a/src/Database/Driver/Sqlserver.php
+++ b/src/Database/Driver/Sqlserver.php
@@ -21,6 +21,7 @@
 use Cake\Database\Expression\FunctionExpression;
 use Cake\Database\Expression\OrderByExpression;
 use Cake\Database\Expression\OrderClauseExpression;
+use Cake\Database\Expression\StringAggExpression;
 use Cake\Database\Expression\TupleComparison;
 use Cake\Database\Expression\UnaryExpression;
 use Cake\Database\ExpressionInterface;
@@ -284,8 +285,12 @@ public function supports(DriverFeatureEnum $feature): bool
             DriverFeatureEnum::SAVEPOINT,
             DriverFeatureEnum::TRUNCATE_WITH_CONSTRAINTS,
             DriverFeatureEnum::WINDOW => true,
+            DriverFeatureEnum::STRING_AGG => version_compare($this->version(), '14', '>='),
+            DriverFeatureEnum::GROUP_CONCAT => false,
             DriverFeatureEnum::INTERSECT => true,
             DriverFeatureEnum::INTERSECT_ALL => false,
+            DriverFeatureEnum::EXCEPT => true,
+            DriverFeatureEnum::EXCEPT_ALL => false,
             DriverFeatureEnum::JSON => false,
             DriverFeatureEnum::SET_OPERATIONS_ORDER_BY => false,
             DriverFeatureEnum::OPTIMIZER_HINT_COMMENT => false,
@@ -466,11 +471,26 @@ protected function _transformDistinct(SelectQuery $query): SelectQuery
     protected function _expressionTranslators(): array
     {
         return [
+            StringAggExpression::class => '_transformStringAggExpression',
             FunctionExpression::class => '_transformFunctionExpression',
             TupleComparison::class => '_transformTupleComparison',
         ];
     }
 
+    /**
+     * Receives a StringAggExpression and changes it so that it conforms to this
+     * SQL dialect.
+     *
+     * @param \Cake\Database\Expression\StringAggExpression $expression The expression to convert to TSQL.
+     * @return void
+     */
+    protected function _transformStringAggExpression(StringAggExpression $expression): void
+    {
+        $expression
+            ->setName('STRING_AGG')
+            ->setSyntax(StringAggExpression::SYNTAX_WITHIN_GROUP);
+    }
+
     /**
      * Receives a FunctionExpression and changes it so that it conforms to this
      * SQL dialect.
diff --git a/src/Database/DriverFeatureEnum.php b/src/Database/DriverFeatureEnum.php
index 15219158c10..e329e6e4bac 100644
--- a/src/Database/DriverFeatureEnum.php
+++ b/src/Database/DriverFeatureEnum.php
@@ -59,7 +59,17 @@ enum DriverFeatureEnum: string
     case INTERSECT_ALL = 'intersect-all';
 
     /**
-     * Support for order by in set operations (union, intersect)
+     * Except feature support
+     */
+    case EXCEPT = 'except';
+
+    /**
+     * Except all feature support
+     */
+    case EXCEPT_ALL = 'except-all';
+
+    /**
+     * Support for order by in set operations (union, intersect, except)
      */
     case SET_OPERATIONS_ORDER_BY = 'set-operations-order-by';
 
@@ -72,4 +82,14 @@ enum DriverFeatureEnum: string
      * Support for CHECK constraints.
      */
     case CHECK_CONSTRAINTS = 'check-constraints';
+
+    /**
+     * String aggregation via STRING_AGG support.
+     */
+    case STRING_AGG = 'string-agg';
+
+    /**
+     * String aggregation via GROUP_CONCAT support.
+     */
+    case GROUP_CONCAT = 'group-concat';
 }
diff --git a/src/Database/Expression/BetweenExpression.php b/src/Database/Expression/BetweenExpression.php
index 253fc12be41..db66959c835 100644
--- a/src/Database/Expression/BetweenExpression.php
+++ b/src/Database/Expression/BetweenExpression.php
@@ -50,6 +50,13 @@ class BetweenExpression implements ExpressionInterface, FieldInterface
      */
     protected mixed $_type;
 
+    /**
+     * Whether this is a NOT BETWEEN expression
+     *
+     * @var bool
+     */
+    protected bool $_not = false;
+
     /**
      * Constructor
      *
@@ -57,9 +64,15 @@ class BetweenExpression implements ExpressionInterface, FieldInterface
      * @param mixed $from The initial value of the range.
      * @param mixed $to The ending value in the comparison range.
      * @param string|null $type The data type name to bind the values with.
+     * @param bool $not Whether this is a NOT BETWEEN expression.
      */
-    public function __construct(ExpressionInterface|string $field, mixed $from, mixed $to, ?string $type = null)
-    {
+    public function __construct(
+        ExpressionInterface|string $field,
+        mixed $from,
+        mixed $to,
+        ?string $type = null,
+        bool $not = false,
+    ) {
         if ($type !== null) {
             $from = $this->_castToExpression($from, $type);
             $to = $this->_castToExpression($to, $type);
@@ -69,6 +82,7 @@ public function __construct(ExpressionInterface|string $field, mixed $from, mixe
         $this->_from = $from;
         $this->_to = $to;
         $this->_type = $type;
+        $this->_not = $not;
     }
 
     /**
@@ -95,7 +109,9 @@ public function sql(ValueBinder $binder): string
         }
         assert(is_string($field));
 
-        return sprintf('%s BETWEEN %s AND %s', $field, $parts['from'], $parts['to']);
+        $operator = $this->_not ? 'NOT BETWEEN' : 'BETWEEN';
+
+        return sprintf('%s %s %s AND %s', $field, $operator, $parts['from'], $parts['to']);
     }
 
     /**
diff --git a/src/Database/Expression/DistinctComparisonExpression.php b/src/Database/Expression/DistinctComparisonExpression.php
new file mode 100644
index 00000000000..541d668cf4c
--- /dev/null
+++ b/src/Database/Expression/DistinctComparisonExpression.php
@@ -0,0 +1,74 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Database\Expression;
+
+use Cake\Database\ExpressionInterface;
+use Cake\Database\ValueBinder;
+
+/**
+ * A Comparison is a type of query expression that represents `IS DISTINCT FROM`
+ * or `IS NOT DISTINCT FROM` operations.
+ */
+class DistinctComparisonExpression extends ComparisonExpression
+{
+    /**
+     * Whether to wrap the expression in `NOT (...)`
+     *
+     * @var bool
+     */
+    protected bool $isNot = false;
+
+    /**
+     * Sets whether to wrap the expression in `NOT (...)`
+     *
+     * @param bool $not Whether to wrap the expression in `NOT (...)`
+     * @return $this
+     */
+    public function setNot(bool $not)
+    {
+        $this->isNot = $not;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function sql(ValueBinder $binder): string
+    {
+        $field = $this->_field;
+
+        if ($field instanceof ExpressionInterface) {
+            $field = $field->sql($binder);
+        }
+
+        if ($this->_value instanceof IdentifierExpression) {
+            $template = '%s %s %s';
+            $value = $this->_value->sql($binder);
+        } elseif ($this->_value instanceof ExpressionInterface) {
+            $template = '%s %s (%s)';
+            $value = $this->_value->sql($binder);
+        } else {
+            [$template, $value] = $this->_stringExpression($binder);
+        }
+
+        /** @var string $field */
+        $sql = sprintf($template, $field, $this->_operator, $value);
+
+        return $this->isNot ? "NOT ({$sql})" : $sql;
+    }
+}
diff --git a/src/Database/Expression/QueryExpression.php b/src/Database/Expression/QueryExpression.php
index 1140e623bfc..c5cdeb1f294 100644
--- a/src/Database/Expression/QueryExpression.php
+++ b/src/Database/Expression/QueryExpression.php
@@ -259,6 +259,36 @@ public function isNotNull(ExpressionInterface|string $field)
         return $this->add(new UnaryExpression('IS NOT NULL', $field, UnaryExpression::POSTFIX));
     }
 
+    /**
+     * Adds a new condition to the expression object in the form "field IS DISTINCT FROM value".
+     *
+     * @param \Cake\Database\ExpressionInterface|string $field Database field to be compared against value
+     * @param mixed $value The value to be bound to $field for comparison
+     * @param string|null $type the type name for $value as configured using the Type map.
+     * @return $this
+     */
+    public function isDistinctFrom(ExpressionInterface|string $field, mixed $value, ?string $type = null)
+    {
+        $type ??= $this->_calculateType($field);
+
+        return $this->add(new DistinctComparisonExpression($field, $value, $type, 'IS DISTINCT FROM'));
+    }
+
+    /**
+     * Adds a new condition to the expression object in the form "field IS NOT DISTINCT FROM value".
+     *
+     * @param \Cake\Database\ExpressionInterface|string $field Database field to be compared against value
+     * @param mixed $value The value to be bound to $field for comparison
+     * @param string|null $type the type name for $value as configured using the Type map.
+     * @return $this
+     */
+    public function isNotDistinctFrom(ExpressionInterface|string $field, mixed $value, ?string $type = null)
+    {
+        $type ??= $this->_calculateType($field);
+
+        return $this->add(new DistinctComparisonExpression($field, $value, $type, 'IS NOT DISTINCT FROM'));
+    }
+
     /**
      * Adds a new condition to the expression object in the form "field LIKE value".
      *
@@ -365,6 +395,28 @@ public function notIn(
         return $this->add(new ComparisonExpression($field, $values, $type, 'NOT IN'));
     }
 
+    /**
+     * Adds a new condition to the expression object in the form
+     * "(field IN (value1, value2) OR field IS NULL".
+     *
+     * @param \Cake\Database\ExpressionInterface|string $field Database field to be compared against value
+     * @param \Cake\Database\ExpressionInterface|array|string $values the value to be bound to $field for comparison
+     * @param string|null $type the type name for $value as configured using the Type map.
+     * @return $this
+     */
+    public function inOrNull(
+        ExpressionInterface|string $field,
+        ExpressionInterface|array|string $values,
+        ?string $type = null,
+    ) {
+        $or = new static([], $this->getTypeMap(), 'OR');
+        $or
+            ->in($field, $values, $type)
+            ->isNull($field);
+
+        return $this->add($or);
+    }
+
     /**
      * Adds a new condition to the expression object in the form
      * "(field NOT IN (value1, value2) OR field IS NULL".
@@ -379,7 +431,7 @@ public function notInOrNull(
         ExpressionInterface|array|string $values,
         ?string $type = null,
     ) {
-        $or = new static([], [], 'OR');
+        $or = new static([], $this->getTypeMap(), 'OR');
         $or
             ->notIn($field, $values, $type)
             ->isNull($field);
@@ -426,6 +478,23 @@ public function between(ExpressionInterface|string $field, mixed $from, mixed $t
         return $this->add(new BetweenExpression($field, $from, $to, $type));
     }
 
+    /**
+     * Adds a new condition to the expression object in the form
+     * "field NOT BETWEEN from AND to".
+     *
+     * @param \Cake\Database\ExpressionInterface|string $field The field name to compare for values outside the range.
+     * @param mixed $from The initial value of the range.
+     * @param mixed $to The ending value in the comparison range.
+     * @param string|null $type the type name for $value as configured using the Type map.
+     * @return $this
+     */
+    public function notBetween(ExpressionInterface|string $field, mixed $from, mixed $to, ?string $type = null)
+    {
+        $type ??= $this->_calculateType($field);
+
+        return $this->add(new BetweenExpression($field, $from, $to, $type, true));
+    }
+
     /**
      * Returns a new QueryExpression object containing all the conditions passed
      * and set up the conjunction to be "AND"
@@ -690,12 +759,18 @@ protected function _parseCondition(string $condition, mixed $value): ExpressionI
         // like `CONCAT(first_name, ' ', last_name) IN`.
         if ($spaces > 1) {
             $parts = explode(' ', $expression);
-            if (preg_match('/(is not|not \w+)$/i', $expression)) {
-                $last = array_pop($parts);
-                $second = array_pop($parts);
-                $parts[] = "{$second} {$last}";
+            if (preg_match('/is not distinct from$/i', $expression)) {
+                $operator = implode(' ', array_slice($parts, -4));
+                $parts = array_slice($parts, 0, -4);
+            } elseif (preg_match('/is distinct from$/i', $expression)) {
+                $operator = implode(' ', array_slice($parts, -3));
+                $parts = array_slice($parts, 0, -3);
+            } elseif (preg_match('/(is not|not \w+)$/i', $expression)) {
+                $operator = implode(' ', array_slice($parts, -2));
+                $parts = array_slice($parts, 0, -2);
+            } else {
+                $operator = array_pop($parts);
             }
-            $operator = array_pop($parts);
             $expression = implode(' ', $parts);
         } elseif ($spaces === 1) {
             $parts = explode(' ', $expression, 2);
@@ -743,11 +818,18 @@ protected function _parseCondition(string $condition, mixed $value): ExpressionI
             $operator = '!=';
         }
 
-        if ($value === null && $this->_conjunction !== ',') {
+        if (in_array($operator, ['IS DISTINCT FROM', 'IS NOT DISTINCT FROM'], true)) {
+            return new DistinctComparisonExpression($expression, $value, $type, $operator);
+        }
+
+        if (
+            $value === null &&
+            $this->_conjunction !== ','
+        ) {
             throw new InvalidArgumentException(
                 sprintf(
                     'Expression `%s` has invalid `null` value.'
-                    . ' If `null` is a valid value, operator (IS, IS NOT) is missing.',
+                    . ' If `null` is a valid value, operator (IS, IS NOT, IS DISTINCT FROM, IS NOT DISTINCT FROM) is missing.',
                     $expression,
                 ),
             );
diff --git a/src/Database/Expression/StringAggExpression.php b/src/Database/Expression/StringAggExpression.php
new file mode 100644
index 00000000000..f842be6b37c
--- /dev/null
+++ b/src/Database/Expression/StringAggExpression.php
@@ -0,0 +1,205 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Database\Expression;
+
+use Cake\Database\ExpressionInterface;
+use Cake\Database\Query;
+use Cake\Database\ValueBinder;
+use Closure;
+use InvalidArgumentException;
+
+/**
+ * Portable string aggregation expression that can render as STRING_AGG or
+ * GROUP_CONCAT depending on the driver dialect.
+ */
+class StringAggExpression extends AggregateExpression
+{
+    public const SYNTAX_STANDARD = 'standard';
+    public const SYNTAX_WITHIN_GROUP = 'within-group';
+    public const SYNTAX_GROUP_CONCAT = 'group-concat';
+
+    /**
+     * Aggregate-local ORDER BY clause.
+     *
+     * @var \Cake\Database\Expression\OrderByExpression|null
+     */
+    protected ?OrderByExpression $aggregateOrderBy = null;
+
+    /**
+     * SQL syntax variant to render.
+     *
+     * @var string
+     */
+    protected string $syntax = self::SYNTAX_STANDARD;
+
+    /**
+     * Constructor.
+     *
+     * @param array $params Function arguments, value first and separator second.
+     * @param array<string, string>|array<string|null> $types Types for function arguments.
+     * @param \Cake\Database\ExpressionInterface|array|string|null $orderBy Aggregate-local ordering.
+     */
+    public function __construct(array $params = [], array $types = [], ExpressionInterface|array|string|null $orderBy = null)
+    {
+        parent::__construct('STRING_AGG', $params, $types);
+        if ($orderBy !== null) {
+            $this->setAggregateOrderBy($orderBy);
+        }
+    }
+
+    /**
+     * Sets aggregate-local ordering.
+     *
+     * @param \Cake\Database\ExpressionInterface|array|string $fields The sort columns.
+     * @return $this
+     */
+    public function setAggregateOrderBy(ExpressionInterface|array|string $fields)
+    {
+        $this->aggregateOrderBy ??= new OrderByExpression();
+        $this->aggregateOrderBy->add($fields);
+
+        return $this;
+    }
+
+    /**
+     * Sets the SQL syntax variant.
+     *
+     * @param string $syntax The syntax variant.
+     * @return $this
+     */
+    public function setSyntax(string $syntax)
+    {
+        $allowed = [
+            static::SYNTAX_STANDARD,
+            static::SYNTAX_WITHIN_GROUP,
+            static::SYNTAX_GROUP_CONCAT,
+        ];
+        if (!in_array($syntax, $allowed, true)) {
+            throw new InvalidArgumentException(sprintf('Unsupported string aggregation syntax `%s`.', $syntax));
+        }
+
+        $this->syntax = $syntax;
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function sql(ValueBinder $binder): string
+    {
+        $parts = array_map(fn($part) => $this->stringifyPart($part, $binder), $this->_conditions);
+        [$value, $separator] = $parts + [null, null];
+
+        $sql = match ($this->syntax) {
+            static::SYNTAX_GROUP_CONCAT => $this->_name . sprintf(
+                '(%s%s SEPARATOR %s)',
+                $value,
+                $this->aggregateOrderBy ? ' ' . $this->aggregateOrderBy->sql($binder) : '',
+                $separator,
+            ),
+            static::SYNTAX_WITHIN_GROUP => $this->_name . sprintf(
+                '(%s, %s)%s',
+                $value,
+                $separator,
+                $this->aggregateOrderBy ? ' WITHIN GROUP (' . $this->aggregateOrderBy->sql($binder) . ')' : '',
+            ),
+            default => $this->_name . sprintf(
+                '(%s, %s%s)',
+                $value,
+                $separator,
+                $this->aggregateOrderBy ? ' ' . $this->aggregateOrderBy->sql($binder) : '',
+            ),
+        };
+
+        if ($this->filter !== null) {
+            $sql .= ' FILTER (WHERE ' . $this->filter->sql($binder) . ')';
+        }
+        if ($this->window !== null) {
+            if ($this->window->isNamedOnly()) {
+                $sql .= ' OVER ' . $this->window->sql($binder);
+            } else {
+                $sql .= ' OVER (' . $this->window->sql($binder) . ')';
+            }
+        }
+
+        return $sql;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function traverse(Closure $callback)
+    {
+        parent::traverse($callback);
+        if ($this->aggregateOrderBy !== null) {
+            $callback($this->aggregateOrderBy);
+            $this->aggregateOrderBy->traverse($callback);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function count(): int
+    {
+        $count = parent::count();
+        if ($this->aggregateOrderBy !== null) {
+            $count += 1;
+        }
+
+        return $count;
+    }
+
+    /**
+     * Clone this object and its subtree of expressions.
+     */
+    public function __clone()
+    {
+        parent::__clone();
+        if ($this->aggregateOrderBy !== null) {
+            $this->aggregateOrderBy = clone $this->aggregateOrderBy;
+        }
+    }
+
+    /**
+     * Converts a function argument into SQL.
+     *
+     * @param mixed $part Function argument.
+     * @param \Cake\Database\ValueBinder $binder Value binder.
+     * @return string
+     */
+    protected function stringifyPart(mixed $part, ValueBinder $binder): string
+    {
+        if ($part instanceof Query) {
+            return sprintf('(%s)', $part->sql($binder));
+        }
+        if ($part instanceof ExpressionInterface) {
+            return $part->sql($binder);
+        }
+        if (is_array($part)) {
+            $placeholder = $binder->placeholder('param');
+            $binder->bind($placeholder, $part['value'], $part['type']);
+
+            return $placeholder;
+        }
+
+        return (string)$part;
+    }
+}
diff --git a/src/Database/FunctionsBuilder.php b/src/Database/FunctionsBuilder.php
index 2afbc46b53b..12cb0cf1684 100644
--- a/src/Database/FunctionsBuilder.php
+++ b/src/Database/FunctionsBuilder.php
@@ -18,6 +18,7 @@
 
 use Cake\Database\Expression\AggregateExpression;
 use Cake\Database\Expression\FunctionExpression;
+use Cake\Database\Expression\StringAggExpression;
 use InvalidArgumentException;
 
 /**
@@ -102,6 +103,27 @@ public function count(ExpressionInterface|string $expression, array $types = [])
         return $this->aggregate('COUNT', $this->toLiteralParam($expression), $types, 'integer');
     }
 
+    /**
+     * Returns an AggregateExpression representing a portable string aggregation call.
+     *
+     * @param \Cake\Database\ExpressionInterface|string $expression The value to aggregate.
+     * @param string $separator The separator inserted between values.
+     * @param \Cake\Database\ExpressionInterface|array|string|null $orderBy Aggregate-local ordering.
+     * @param array $types List of types to bind to the arguments.
+     * @return \Cake\Database\Expression\StringAggExpression
+     */
+    public function stringAgg(
+        ExpressionInterface|string $expression,
+        string $separator,
+        ExpressionInterface|array|string|null $orderBy = null,
+        array $types = [],
+    ): StringAggExpression {
+        $params = $this->toLiteralParam($expression);
+        $params[] = $separator;
+
+        return new StringAggExpression($params, $types, $orderBy);
+    }
+
     /**
      * Returns a FunctionExpression representing a string concatenation
      *
diff --git a/src/Database/Query.php b/src/Database/Query.php
index 359907ce874..923a9889548 100644
--- a/src/Database/Query.php
+++ b/src/Database/Query.php
@@ -121,6 +121,7 @@ abstract class Query implements ExpressionInterface, Stringable
         'limit' => null,
         'offset' => null,
         'union' => [],
+        'except' => [],
         'epilog' => null,
         'intersect' => [],
     ];
diff --git a/src/Database/Query/SelectQuery.php b/src/Database/Query/SelectQuery.php
index b72c5d72139..8f601ac7309 100644
--- a/src/Database/Query/SelectQuery.php
+++ b/src/Database/Query/SelectQuery.php
@@ -68,6 +68,7 @@ class SelectQuery extends Query implements IteratorAggregate
         'limit' => null,
         'offset' => null,
         'union' => [],
+        'except' => [],
         'epilog' => null,
         'intersect' => [],
     ];
@@ -568,6 +569,79 @@ public function intersectAll(Query|string $query, bool $overwrite = false)
         return $this;
     }
 
+    /**
+     * Adds a complete query to be used in conjunction with an EXCEPT operator with
+     * this query. This is used to subtract the passed query from the result set of this query.
+     * You can add as many queries as you required by calling multiple times
+     * this method with different queries.
+     *
+     * By default, the EXCEPT operator will remove duplicate rows, if you wish to include
+     * every row for all queries, use exceptAll().
+     *
+     * ### Examples
+     *
+     * ```
+     * $except = (new SelectQuery($conn))->select(['id', 'title'])->from(['a' => 'articles']);
+     * $query->select(['id', 'name'])->from(['d' => 'things'])->except($except);
+     * ```
+     *
+     * Will produce:
+     *
+     * `SELECT id, name FROM things d EXCEPT SELECT id, title FROM articles a`
+     *
+     * @param \Cake\Database\Query|string $query full SQL query to be used in EXCEPT operator
+     * @param bool $overwrite whether to reset the list of queries to be operated or not
+     * @return $this
+     */
+    public function except(Query|string $query, bool $overwrite = false)
+    {
+        if ($overwrite) {
+            $this->_parts['except'] = [];
+        }
+        $this->_parts['except'][] = [
+            'all' => false,
+            'query' => $query,
+        ];
+        $this->_dirty();
+
+        return $this;
+    }
+
+    /**
+     * Adds a complete query to be used in conjunction with the EXCEPT ALL operator with
+     * this query. This is used to subtract the passed query from the result set of this query.
+     * You can add as many queries as you required by calling multiple times
+     * this method with different queries.
+     *
+     * Unlike EXCEPT, EXCEPT ALL will not remove duplicate rows.
+     *
+     * ```
+     * $except = (new SelectQuery($conn))->select(['id', 'title'])->from(['a' => 'articles']);
+     * $query->select(['id', 'name'])->from(['d' => 'things'])->exceptAll($except);
+     * ```
+     *
+     * Will produce:
+     *
+     * `SELECT id, name FROM things d EXCEPT ALL SELECT id, title FROM articles a`
+     *
+     * @param \Cake\Database\Query|string $query full SQL query to be used in EXCEPT operator
+     * @param bool $overwrite whether to reset the list of queries to be operated or not
+     * @return $this
+     */
+    public function exceptAll(Query|string $query, bool $overwrite = false)
+    {
+        if ($overwrite) {
+            $this->_parts['except'] = [];
+        }
+        $this->_parts['except'][] = [
+            'all' => true,
+            'query' => $query,
+        ];
+        $this->_dirty();
+
+        return $this;
+    }
+
     /**
      * Executes this query and returns a results iterator. This function is required
      * for implementing the IteratorAggregate interface and allows the query to be
diff --git a/src/Database/QueryCompiler.php b/src/Database/QueryCompiler.php
index 181e15c6cf0..3be56131535 100644
--- a/src/Database/QueryCompiler.php
+++ b/src/Database/QueryCompiler.php
@@ -53,7 +53,7 @@ class QueryCompiler
      */
     protected array $_selectParts = [
         'comment', 'with', 'select', 'from', 'join', 'where', 'group', 'having', 'window', 'order',
-        'limit', 'offset', 'union', 'epilog', 'intersect',
+        'limit', 'offset', 'union', 'except', 'epilog', 'intersect',
     ];
 
     /**
@@ -191,7 +191,7 @@ protected function _buildSelectPart(array $parts, Query $query, ValueBinder $bin
         $driver = $query->getDriver();
         $select = 'SELECT%s%s %s%s';
         if (
-            ($query->clause('union') || $query->clause('intersect')) &&
+            ($query->clause('union') || $query->clause('except') || $query->clause('intersect')) &&
             $driver->supports(DriverFeatureEnum::SET_OPERATIONS_ORDER_BY)
         ) {
             $select = '(SELECT%s%s %s%s';
@@ -396,6 +396,21 @@ protected function _buildIntersectPart(array $parts, Query $query, ValueBinder $
         return $this->_buildSetOperationPart('INTERSECT', $parts, $query, $binder);
     }
 
+    /**
+     * Builds the SQL string for all the EXCEPT clauses in this query, when dealing
+     * with query objects it will also transform them using their configured SQL
+     * dialect.
+     *
+     * @param array $parts list of queries to be operated with EXCEPT
+     * @param \Cake\Database\Query $query The query that is being compiled
+     * @param \Cake\Database\ValueBinder $binder Value binder used to generate parameter placeholder
+     * @return string
+     */
+    protected function _buildExceptPart(array $parts, Query $query, ValueBinder $binder): string
+    {
+        return $this->_buildSetOperationPart('EXCEPT', $parts, $query, $binder);
+    }
+
     /**
      * Builds the SQL string for all the UNION clauses in this query, when dealing
      * with query objects it will also transform them using their configured SQL
diff --git a/src/Database/Schema/Column.php b/src/Database/Schema/Column.php
index 3706ee67548..0a3d0400bf4 100644
--- a/src/Database/Schema/Column.php
+++ b/src/Database/Schema/Column.php
@@ -46,6 +46,7 @@ class Column
      * @param bool|null $unsigned Whether the column is unsigned
      * @param string|null $collate Collation for the column
      * @param int|null $srid SRID for geometry fields
+     * @param string|null $geometryType Geometry type for geometry fields (e.g., Point, Polygon)
      * @param string|null $baseType The basic schema type if the column type is a complex/custom type.
      * @param bool|null $fixed Whether the column is fixed-length (BINARY vs VARBINARY)
      */
@@ -65,6 +66,7 @@ public function __construct(
         protected ?bool $unsigned = null,
         protected ?string $collate = null,
         protected ?int $srid = null,
+        protected ?string $geometryType = null,
         protected ?string $baseType = null,
         protected ?bool $fixed = null,
     ) {
@@ -505,6 +507,29 @@ public function getSrid(): ?int
         return $this->srid;
     }
 
+    /**
+     * Sets the geometry type for geometry fields.
+     *
+     * @param string $geometryType Geometry type (e.g., Point, Polygon)
+     * @return $this
+     */
+    public function setGeometryType(string $geometryType)
+    {
+        $this->geometryType = $geometryType;
+
+        return $this;
+    }
+
+    /**
+     * Gets the geometry type for geometry fields.
+     *
+     * @return string|null
+     */
+    public function getGeometryType(): ?string
+    {
+        return $this->geometryType;
+    }
+
     /**
      * Sets whether the column is fixed-length.
      *
@@ -562,6 +587,7 @@ protected function getValidOptions(): array
             'properties',
             'collate',
             'srid',
+            'geometryType',
             'increment',
             'generated',
             'fixed',
@@ -612,7 +638,7 @@ public function toArray(): array
             }
         }
 
-        return [
+        $result = [
             'name' => $this->getName(),
             'baseType' => $this->getBaseType(),
             'type' => $type,
@@ -630,5 +656,12 @@ public function toArray(): array
             'identity' => $this->getIdentity(),
             'fixed' => $this->getFixed(),
         ];
+
+        // Only include geometryType when set (for PostGIS reflection)
+        if ($this->getGeometryType() !== null) {
+            $result['geometryType'] = $this->getGeometryType();
+        }
+
+        return $result;
     }
 }
diff --git a/src/Database/Schema/Index.php b/src/Database/Schema/Index.php
index 83111e65511..9391530ebf0 100644
--- a/src/Database/Schema/Index.php
+++ b/src/Database/Schema/Index.php
@@ -38,6 +38,17 @@ class Index
      */
     public const FULLTEXT = 'fulltext';
 
+    /**
+     * PostgreSQL index access methods
+     *
+     * @var string
+     */
+    public const GIN = 'gin';
+    public const GIST = 'gist';
+    public const SPGIST = 'spgist';
+    public const BRIN = 'brin';
+    public const HASH = 'hash';
+
     /**
      * Constructor
      *
@@ -48,6 +59,7 @@ class Index
      * @param array<string>|null $order The sort order of the index columns.
      * @param array<string>|null $include The included columns for covering indexes.
      * @param ?string $where The where clause for partial indexes.
+     * @param ?string $accessMethod The index access method for PostgreSQL (gin, gist, spgist, brin, hash).
      */
     public function __construct(
         protected string $name,
@@ -57,6 +69,7 @@ public function __construct(
         protected ?array $order = null,
         protected ?array $include = null,
         protected ?string $where = null,
+        protected ?string $accessMethod = null,
     ) {
     }
 
@@ -231,6 +244,32 @@ public function getWhere(): ?string
         return $this->where;
     }
 
+    /**
+     * Set the index access method for PostgreSQL.
+     *
+     * PostgreSQL supports multiple index access methods: btree (default),
+     * gin, gist, spgist, brin, and hash.
+     *
+     * @param ?string $accessMethod The access method (gin, gist, spgist, brin, hash).
+     * @return $this
+     */
+    public function setAccessMethod(?string $accessMethod)
+    {
+        $this->accessMethod = $accessMethod;
+
+        return $this;
+    }
+
+    /**
+     * Get the index access method for PostgreSQL.
+     *
+     * @return ?string
+     */
+    public function getAccessMethod(): ?string
+    {
+        return $this->accessMethod;
+    }
+
     /**
      * Utility method that maps an array of index options to this object's methods.
      *
@@ -241,7 +280,7 @@ public function getWhere(): ?string
     public function setAttributes(array $attributes)
     {
         // Valid Options
-        $validOptions = ['columns', 'type', 'name', 'length', 'order', 'include', 'where'];
+        $validOptions = ['columns', 'type', 'name', 'length', 'order', 'include', 'where', 'accessMethod'];
         foreach ($attributes as $attr => $value) {
             if (!in_array($attr, $validOptions, true)) {
                 throw new RuntimeException(sprintf('"%s" is not a valid index option.', $attr));
@@ -260,7 +299,7 @@ public function setAttributes(array $attributes)
      */
     public function toArray(): array
     {
-        return [
+        $result = [
             'name' => $this->getName(),
             'columns' => $this->getColumns(),
             'type' => $this->getType(),
@@ -269,5 +308,11 @@ public function toArray(): array
             'include' => $this->getInclude(),
             'where' => $this->getWhere(),
         ];
+        // Only include accessMethod when set (PostgreSQL-specific)
+        if ($this->accessMethod !== null) {
+            $result['accessMethod'] = $this->accessMethod;
+        }
+
+        return $result;
     }
 }
diff --git a/src/Database/Schema/PostgresSchemaDialect.php b/src/Database/Schema/PostgresSchemaDialect.php
index 0357240baa4..beef53a022c 100644
--- a/src/Database/Schema/PostgresSchemaDialect.php
+++ b/src/Database/Schema/PostgresSchemaDialect.php
@@ -111,6 +111,27 @@ private function describeColumnQuery(): string
         ORDER BY ordinal_position';
     }
 
+    /**
+     * Describes PostGIS specific column information.
+     *
+     * @return array<string, array{name: string, type: string, srid: int}> The column information.
+     */
+    private function describePostgisColumns(string $postgisType, string $table, string $schema, string $catalog): array
+    {
+        $sql = <<<SQL
+            SELECT
+                f_{$postgisType}_column AS name,
+                type,
+                srid
+            FROM public.{$postgisType}_columns
+            WHERE f_table_name = ? AND f_table_schema = ? AND f_table_catalog = ?
+            SQL;
+
+        $columns = $this->_driver->execute($sql, [$table, $schema, $catalog])->fetchAll('assoc');
+
+        return array_combine(array_column($columns, 'name'), $columns);
+    }
+
     /**
      * Convert a column definition to the abstract types.
      *
@@ -279,9 +300,18 @@ public function describeColumns(string $tableName): array
         [$schema, $name] = $this->splitTablename($tableName);
 
         $sql = $this->describeColumnQuery();
-        $statement = $this->_driver->execute($sql, [$name, $schema, $config['database']]);
+        $rows = $this->_driver->execute($sql, [$name, $schema, $config['database']])->fetchAll('assoc');
+
+        $postgisColumns = [];
+        $udtTypes = array_column($rows, 'udt_name');
+        foreach (['geometry', 'geography'] as $postgisType) {
+            if (in_array($postgisType, $udtTypes)) {
+                $postgisColumns += $this->describePostgisColumns($postgisType, $name, $schema, $config['database']);
+            }
+        }
+
         $columns = [];
-        foreach ($statement->fetchAll('assoc') as $row) {
+        foreach ($rows as $row) {
             $type = $row['type'];
             if ($type === 'USER-DEFINED') {
                 $type = $row['udt_name'];
@@ -326,6 +356,12 @@ public function describeColumns(string $tableName): array
                 $field['generated'] = $row['identity_generation'];
             }
 
+            // Add PostGIS metadata for geometry/geography columns
+            if (isset($postgisColumns[$row['name']])) {
+                $field['geometryType'] = ucfirst(strtolower($postgisColumns[$row['name']]['type']));
+                $field['srid'] = $postgisColumns[$row['name']]['srid'];
+            }
+
             $columns[] = $field;
         }
 
@@ -375,12 +411,14 @@ private function describeIndexQuery(): string
         a.attname,
         i.indisprimary,
         i.indisunique,
-        i.indnkeyatts
+        i.indnkeyatts,
+        am.amname
         FROM pg_catalog.pg_namespace n
         INNER JOIN pg_catalog.pg_class c ON (n.oid = c.relnamespace)
         INNER JOIN pg_catalog.pg_index i ON (c.oid = i.indrelid)
         INNER JOIN pg_catalog.pg_class c2 ON (c2.oid = i.indexrelid)
         INNER JOIN pg_catalog.pg_attribute a ON (a.attrelid = c.oid AND i.indrelid::regclass = a.attrelid::regclass)
+        INNER JOIN pg_catalog.pg_am am ON (c2.relam = am.oid)
         WHERE n.nspname = ?
         AND a.attnum = ANY(i.indkey)
         AND c.relname = ?
@@ -423,6 +461,11 @@ public function convertIndexDescription(TableSchema $schema, array $row): void
                 'type' => $type,
                 'columns' => [],
             ];
+            // Include access method for non-btree indexes
+            $accessMethod = $row['amname'] ?? 'btree';
+            if ($accessMethod !== 'btree') {
+                $index['accessMethod'] = $accessMethod;
+            }
         }
         $index['columns'][] = $row['attname'];
         $schema->addIndex($name, $index);
@@ -458,6 +501,11 @@ public function describeIndexes(string $tableName): array
                     'columns' => [],
                     'length' => [],
                 ];
+                // Include access method for non-btree indexes
+                $accessMethod = $row['amname'] ?? 'btree';
+                if ($accessMethod !== 'btree') {
+                    $indexes[$name]['accessMethod'] = $accessMethod;
+                }
             }
             if ($constraint) {
                 $indexes[$name]['constraint'] = $constraint;
@@ -917,6 +965,14 @@ public function indexSql(TableSchema $schema, string $name): string
             $this->_driver->quoteIdentifier(...),
             (array)$index->getColumns(),
         );
+
+        // Build USING clause for non-btree access methods (gin, gist, spgist, brin, hash)
+        $using = '';
+        $accessMethod = $index->getAccessMethod();
+        if ($accessMethod !== null) {
+            $using = ' USING ' . $accessMethod;
+        }
+
         $include = '';
         if ($index->getInclude()) {
             $included = array_map(
@@ -927,9 +983,10 @@ public function indexSql(TableSchema $schema, string $name): string
         }
 
         return sprintf(
-            'CREATE INDEX %s ON %s (%s)%s',
+            'CREATE INDEX %s ON %s%s (%s)%s',
             $this->_driver->quoteIdentifier($name),
             $this->_driver->quoteIdentifier($schema->name()),
+            $using,
             implode(', ', $columns),
             $include,
         );
diff --git a/src/Database/Schema/TableSchema.php b/src/Database/Schema/TableSchema.php
index 49c7b4479c7..6dcaf60b148 100644
--- a/src/Database/Schema/TableSchema.php
+++ b/src/Database/Schema/TableSchema.php
@@ -172,15 +172,23 @@ class TableSchema implements TableSchemaInterface, SqlGeneratorInterface
             'unsigned' => null,
         ],
         'geometry' => [
+            'geometryType' => null,
+            'srid' => null,
+        ],
+        'geography' => [
+            'geometryType' => null,
             'srid' => null,
         ],
         'point' => [
+            'geometryType' => null,
             'srid' => null,
         ],
         'linestring' => [
+            'geometryType' => null,
             'srid' => null,
         ],
         'polygon' => [
+            'geometryType' => null,
             'srid' => null,
         ],
         'datetime' => [
@@ -220,6 +228,7 @@ class TableSchema implements TableSchemaInterface, SqlGeneratorInterface
         'constraint' => null,
         'deferrable' => null,
         'expression' => null,
+        'accessMethod' => null,
     ];
 
     /**
@@ -835,7 +844,7 @@ protected function _checkForeignKey(array $attrs): array
         // Map the backwards compatible attributes in. Need to check for existing instance.
         $attrs['referencedTable'] = $attrs['references'][0];
         $attrs['referencedColumns'] = (array)$attrs['references'][1];
-        unset($attrs['type'], $attrs['references'], $attrs['length'], $attrs['expression']);
+        unset($attrs['type'], $attrs['references'], $attrs['length'], $attrs['expression'], $attrs['accessMethod']);
 
         return $attrs;
     }
diff --git a/src/Database/SqlserverCompiler.php b/src/Database/SqlserverCompiler.php
index e0f15b7d5e0..9cf5b4d1223 100644
--- a/src/Database/SqlserverCompiler.php
+++ b/src/Database/SqlserverCompiler.php
@@ -49,7 +49,7 @@ class SqlserverCompiler extends QueryCompiler
      */
     protected array $_selectParts = [
         'comment', 'with', 'select', 'from', 'join', 'where', 'group', 'having', 'window', 'order',
-        'offset', 'limit', 'union', 'epilog', 'intersect',
+        'offset', 'limit', 'union', 'except', 'epilog', 'intersect',
     ];
 
     /**
diff --git a/src/Database/Type/DecimalType.php b/src/Database/Type/DecimalType.php
index 496bc18c2f1..81a958ebda4 100644
--- a/src/Database/Type/DecimalType.php
+++ b/src/Database/Type/DecimalType.php
@@ -175,12 +175,17 @@ public function useLocaleParser(bool $enable = true)
      * the locale aware parser.
      *
      * @param string $value The value to parse and convert to an float.
-     * @return string
+     * @return string|null
      */
-    protected function _parseValue(string $value): string
+    protected function _parseValue(string $value): ?string
     {
         $class = static::$numberClass;
+        $result = $class::parseFloat($value);
+
+        if ($result === null) {
+            return null;
+        }
 
-        return (string)$class::parseFloat($value);
+        return (string)$result;
     }
 }
diff --git a/src/Database/Type/FloatType.php b/src/Database/Type/FloatType.php
index c976cca6e6e..7c80d3cb3b9 100644
--- a/src/Database/Type/FloatType.php
+++ b/src/Database/Type/FloatType.php
@@ -155,9 +155,9 @@ public function useLocaleParser(bool $enable = true)
      * aware parser.
      *
      * @param string $value The value to parse and convert to an float.
-     * @return float
+     * @return float|null
      */
-    protected function _parseValue(string $value): float
+    protected function _parseValue(string $value): ?float
     {
         $class = static::$numberClass;
 
diff --git a/src/Database/composer.json b/src/Database/composer.json
index 405232f5983..4216e736517 100644
--- a/src/Database/composer.json
+++ b/src/Database/composer.json
@@ -25,14 +25,14 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
         "cakephp/chronos": "^3.3",
-        "cakephp/datasource": "^5.3.0",
+        "cakephp/datasource": "5.4.*@dev",
         "psr/log": "^3.0"
     },
     "require-dev": {
-        "cakephp/i18n": "^5.3.0",
-        "cakephp/log": "^5.3.0"
+        "cakephp/i18n": "5.4.*@dev",
+        "cakephp/log": "5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Datasource/composer.json b/src/Datasource/composer.json
index 57273ee7ce7..aa4f557b92b 100644
--- a/src/Datasource/composer.json
+++ b/src/Datasource/composer.json
@@ -25,13 +25,13 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
         "psr/simple-cache": "^2.0 || ^3.0"
     },
     "require-dev": {
-        "cakephp/cache": "^5.3.0",
-        "cakephp/collection": "^5.3.0",
-        "cakephp/utility": "^5.3.0"
+        "cakephp/cache": "5.4.*@dev",
+        "cakephp/collection": "5.4.*@dev",
+        "cakephp/utility": "5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Event/composer.json b/src/Event/composer.json
index 942616483c2..d4ef7730345 100644
--- a/src/Event/composer.json
+++ b/src/Event/composer.json
@@ -24,7 +24,7 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0"
+        "cakephp/core": "5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Form/composer.json b/src/Form/composer.json
index fecc6fb0ddf..86d018454db 100644
--- a/src/Form/composer.json
+++ b/src/Form/composer.json
@@ -22,8 +22,8 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/event": "^5.3.0",
-        "cakephp/validation":"^5.3.0"
+        "cakephp/event": "5.4.*@dev",
+        "cakephp/validation":"5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Http/BaseApplication.php b/src/Http/BaseApplication.php
index 0a073bb0407..4d464484a59 100644
--- a/src/Http/BaseApplication.php
+++ b/src/Http/BaseApplication.php
@@ -20,8 +20,8 @@
 use Cake\Console\CommandCollection;
 use Cake\Controller\ControllerFactory;
 use Cake\Core\ConsoleApplicationInterface;
-use Cake\Core\Container;
 use Cake\Core\ContainerApplicationInterface;
+use Cake\Core\ContainerFactory;
 use Cake\Core\ContainerInterface;
 use Cake\Core\EventAwareApplicationInterface;
 use Cake\Core\Exception\MissingPluginException;
@@ -291,11 +291,15 @@ public function getContainer(): ContainerInterface
      * Override this method if you need to use a custom container or
      * want to change how the container is built.
      *
+     * The container type is determined by `Configure::read('App.container')`:
+     * - 'cake': Uses the built-in CakePHP container
+     * - Any other value: Uses the League container (default)
+     *
      * @return \Cake\Core\ContainerInterface
      */
     protected function buildContainer(): ContainerInterface
     {
-        $container = new Container();
+        $container = ContainerFactory::create();
         $this->services($container);
         foreach ($this->plugins->with('services') as $plugin) {
             $plugin->services($container);
diff --git a/src/Http/Link/Link.php b/src/Http/Link/Link.php
new file mode 100644
index 00000000000..0d748ce0ca8
--- /dev/null
+++ b/src/Http/Link/Link.php
@@ -0,0 +1,158 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Http\Link;
+
+use Psr\Link\EvolvableLinkInterface;
+use Stringable;
+
+/**
+ * PSR-13 Link implementation.
+ *
+ * Represents a hypermedia link as defined in RFC 5988 and RFC 8288.
+ *
+ * ### Usage
+ *
+ * ```php
+ * $link = new Link('/api/users', 'self');
+ * $link = $link->withRel('collection');
+ * $link = $link->withAttribute('type', 'application/json');
+ * ```
+ */
+class Link implements EvolvableLinkInterface
+{
+    /**
+     * The link relations.
+     *
+     * @var array<string>
+     */
+    private array $rels;
+
+    /**
+     * The link attributes.
+     *
+     * @var array<string, string|bool|int|float|array<string>>
+     */
+    private array $attributes;
+
+    /**
+     * Constructor.
+     *
+     * @param string $href The link URI.
+     * @param array<string>|string $rels The link relation(s).
+     * @param array<string, string|bool|int|float|array<string>> $attributes Additional attributes.
+     */
+    public function __construct(
+        private string $href = '',
+        string|array $rels = [],
+        array $attributes = [],
+    ) {
+        $this->rels = is_string($rels) ? [$rels] : $rels;
+        $this->attributes = $attributes;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getHref(): string
+    {
+        return $this->href;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function isTemplated(): bool
+    {
+        return str_contains($this->href, '{') && str_contains($this->href, '}');
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getRels(): array
+    {
+        return $this->rels;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getAttributes(): array
+    {
+        return $this->attributes;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withHref(string|Stringable $href): static
+    {
+        $new = clone $this;
+        $new->href = (string)$href;
+
+        return $new;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withRel(string $rel): static
+    {
+        $new = clone $this;
+        if (!in_array($rel, $new->rels, true)) {
+            $new->rels[] = $rel;
+        }
+
+        return $new;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withoutRel(string $rel): static
+    {
+        $new = clone $this;
+        $new->rels = array_values(array_filter(
+            $new->rels,
+            fn(string $r): bool => $r !== $rel,
+        ));
+
+        return $new;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withAttribute(string $attribute, string|Stringable|int|float|bool|array $value): static
+    {
+        $new = clone $this;
+        $new->attributes[$attribute] = $value instanceof Stringable ? (string)$value : $value;
+
+        return $new;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withoutAttribute(string $attribute): static
+    {
+        $new = clone $this;
+        unset($new->attributes[$attribute]);
+
+        return $new;
+    }
+}
diff --git a/src/Http/Link/LinkProvider.php b/src/Http/Link/LinkProvider.php
new file mode 100644
index 00000000000..f11804f6294
--- /dev/null
+++ b/src/Http/Link/LinkProvider.php
@@ -0,0 +1,113 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Http\Link;
+
+use Psr\Link\EvolvableLinkProviderInterface;
+use Psr\Link\LinkInterface;
+use Traversable;
+
+/**
+ * PSR-13 LinkProvider implementation.
+ *
+ * Collects and provides hypermedia links.
+ *
+ * ### Usage
+ *
+ * ```php
+ * $provider = new LinkProvider([
+ *     new Link('/api/users', 'self'),
+ *     new Link('/api/users?page=2', 'next'),
+ * ]);
+ *
+ * foreach ($provider->getLinks() as $link) {
+ *     echo $link->getHref();
+ * }
+ * ```
+ */
+class LinkProvider implements EvolvableLinkProviderInterface
+{
+    /**
+     * The links.
+     *
+     * @var array<\Psr\Link\LinkInterface>
+     */
+    private array $links;
+
+    /**
+     * Constructor.
+     *
+     * @param iterable<\Psr\Link\LinkInterface> $links Initial links.
+     */
+    public function __construct(iterable $links = [])
+    {
+        $this->links = $links instanceof Traversable
+            ? iterator_to_array($links)
+            : $links;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getLinks(): iterable
+    {
+        return $this->links;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getLinksByRel(string $rel): iterable
+    {
+        return array_filter(
+            $this->links,
+            fn(LinkInterface $link): bool => in_array($rel, $link->getRels(), true),
+        );
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withLink(LinkInterface $link): static
+    {
+        $new = clone $this;
+
+        // Check if link already exists (by reference)
+        foreach ($new->links as $existing) {
+            if ($existing === $link) {
+                return $new;
+            }
+        }
+
+        $new->links[] = $link;
+
+        return $new;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function withoutLink(LinkInterface $link): static
+    {
+        $new = clone $this;
+        $new->links = array_values(array_filter(
+            $new->links,
+            fn(LinkInterface $l): bool => $l !== $link,
+        ));
+
+        return $new;
+    }
+}
diff --git a/src/Http/Response.php b/src/Http/Response.php
index 29f84f62443..5bed418e66c 100644
--- a/src/Http/Response.php
+++ b/src/Http/Response.php
@@ -20,6 +20,7 @@
 use Cake\Http\Cookie\CookieCollection;
 use Cake\Http\Cookie\CookieInterface;
 use Cake\Http\Exception\NotFoundException;
+use Cake\Http\Link\LinkProvider;
 use Cake\I18n\DateTime as CakeDateTime;
 use DateTime;
 use DateTimeInterface;
@@ -29,6 +30,8 @@
 use Laminas\Diactoros\Stream;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\StreamInterface;
+use Psr\Link\EvolvableLinkProviderInterface;
+use Psr\Link\LinkInterface;
 use SplFileInfo;
 use Stringable;
 use function Cake\Core\env;
@@ -173,6 +176,13 @@ class Response implements ResponseInterface, Stringable
      */
     protected CookieCollection $_cookies;
 
+    /**
+     * Collection of hypermedia links (PSR-13).
+     *
+     * @var \Psr\Link\EvolvableLinkProviderInterface
+     */
+    protected EvolvableLinkProviderInterface $links;
+
     /**
      * Reason Phrase
      *
@@ -231,6 +241,7 @@ public function __construct(array $options = [])
         }
         $this->_setContentType($type);
         $this->_cookies = new CookieCollection();
+        $this->links = new LinkProvider();
     }
 
     /**
@@ -1087,6 +1098,71 @@ public function withCookieCollection(CookieCollection $cookieCollection): static
         return $new;
     }
 
+    /**
+     * Create a new response with a hypermedia link added.
+     *
+     * ### Example
+     *
+     * ```
+     * use Cake\Http\Link\Link;
+     *
+     * $response = $response->withLink(new Link('/api/users', 'self'));
+     * $response = $response->withLink(
+     *     (new Link('/css/app.css'))
+     *         ->withRel('preload')
+     *         ->withAttribute('as', 'style')
+     * );
+     * ```
+     *
+     * @param \Psr\Link\LinkInterface $link The link to add.
+     * @return static
+     */
+    public function withLink(LinkInterface $link): static
+    {
+        $new = clone $this;
+        $new->links = $new->links->withLink($link);
+
+        return $new;
+    }
+
+    /**
+     * Create a new response without a specific hypermedia link.
+     *
+     * @param \Psr\Link\LinkInterface $link The link to remove.
+     * @return static
+     */
+    public function withoutLink(LinkInterface $link): static
+    {
+        $new = clone $this;
+        $new->links = $new->links->withoutLink($link);
+
+        return $new;
+    }
+
+    /**
+     * Get the link provider containing all hypermedia links.
+     *
+     * @return \Psr\Link\EvolvableLinkProviderInterface
+     */
+    public function getLinks(): EvolvableLinkProviderInterface
+    {
+        return $this->links;
+    }
+
+    /**
+     * Get a new instance with provided link provider.
+     *
+     * @param \Psr\Link\EvolvableLinkProviderInterface $links Link provider to set.
+     * @return static
+     */
+    public function withLinkProvider(EvolvableLinkProviderInterface $links): static
+    {
+        $new = clone $this;
+        $new->links = $links;
+
+        return $new;
+    }
+
     /**
      * Get a CorsBuilder instance for defining CORS headers.
      *
@@ -1273,6 +1349,7 @@ public function __debugInfo(): array
             'file' => $this->_file,
             'fileRange' => $this->_fileRange,
             'cookies' => $this->_cookies,
+            'links' => $this->links,
             'cacheDirectives' => $this->_cacheDirectives,
             'body' => (string)$this->getBody(),
         ];
diff --git a/src/Http/ResponseEmitter.php b/src/Http/ResponseEmitter.php
index 30f63682096..5d7f28bb55c 100644
--- a/src/Http/ResponseEmitter.php
+++ b/src/Http/ResponseEmitter.php
@@ -24,6 +24,7 @@
 use Cake\Http\Cookie\CookieInterface;
 use Laminas\Diactoros\RelativeStream;
 use Psr\Http\Message\ResponseInterface;
+use Psr\Link\LinkInterface;
 
 /**
  * Emits a Response to the PHP Server API.
@@ -198,6 +199,73 @@ protected function emitHeaders(ResponseInterface $response): void
         }
 
         $this->emitCookies($cookies);
+        $this->emitLinks($response);
+    }
+
+    /**
+     * Emit PSR-13 links as HTTP Link headers.
+     *
+     * @param \Psr\Http\Message\ResponseInterface $response The response to emit.
+     * @return void
+     */
+    protected function emitLinks(ResponseInterface $response): void
+    {
+        if (!$response instanceof Response) {
+            return;
+        }
+
+        $links = $response->getLinks()->getLinks();
+        foreach ($links as $link) {
+            header(sprintf('Link: %s', $this->formatLink($link)), false);
+        }
+    }
+
+    /**
+     * Format a PSR-13 link as an HTTP Link header value.
+     *
+     * @param \Psr\Link\LinkInterface $link The link to format.
+     * @return string The formatted header value.
+     * @link https://www.rfc-editor.org/rfc/rfc8288 Web Linking (RFC 8288)
+     */
+    protected function formatLink(LinkInterface $link): string
+    {
+        $parts = ['<' . $link->getHref() . '>'];
+
+        $rels = $link->getRels();
+        if ($rels) {
+            $parts[] = 'rel="' . implode(' ', $rels) . '"';
+        }
+
+        foreach ($link->getAttributes() as $key => $value) {
+            if (is_bool($value)) {
+                if ($value) {
+                    $parts[] = $key;
+                }
+                continue;
+            }
+
+            if (is_array($value)) {
+                foreach ($value as $v) {
+                    $parts[] = $key . '="' . $this->escapeHeaderValue((string)$v) . '"';
+                }
+                continue;
+            }
+
+            $parts[] = $key . '="' . $this->escapeHeaderValue((string)$value) . '"';
+        }
+
+        return implode('; ', $parts);
+    }
+
+    /**
+     * Escape a header value for use in a quoted string.
+     *
+     * @param string $value The value to escape.
+     * @return string The escaped value.
+     */
+    protected function escapeHeaderValue(string $value): string
+    {
+        return str_replace(['\\', '"'], ['\\\\', '\\"'], $value);
     }
 
     /**
diff --git a/src/Http/composer.json b/src/Http/composer.json
index 4478048f92e..02f65b4e95c 100644
--- a/src/Http/composer.json
+++ b/src/Http/composer.json
@@ -1,11 +1,12 @@
 {
     "name": "cakephp/http",
-    "description": "CakePHP HTTP client and PSR-7, PSR-15, PSR-17, PSR-18 compliant libraries",
+    "description": "CakePHP HTTP client and PSR-7, PSR-13, PSR-15, PSR-17, PSR-18 compliant libraries",
     "type": "library",
     "keywords": [
         "cakephp",
         "http",
         "PSR-7",
+        "PSR-13",
         "PSR-15",
         "PSR-17",
         "PSR-18"
@@ -26,23 +27,24 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
-        "cakephp/event": "^5.3.0",
-        "cakephp/utility": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
+        "cakephp/event": "5.4.*@dev",
+        "cakephp/utility": "5.4.*@dev",
         "composer/ca-bundle": "^1.5",
         "psr/http-client": "^1.0.2",
         "psr/http-factory": "^1.1",
         "psr/http-message": "^1.1 || ^2.0",
         "psr/http-server-handler": "^1.0.2",
         "psr/http-server-middleware": "^1.0.2",
+        "psr/link": "^2.0",
         "laminas/laminas-diactoros": "^3.8",
         "laminas/laminas-httphandlerrunner": "^2.6"
     },
     "require-dev": {
-        "cakephp/cache": "^5.3.0",
-        "cakephp/console": "^5.3.0",
-        "cakephp/orm": "^5.3.0",
-        "cakephp/i18n": "^5.3.0",
+        "cakephp/cache": "5.4.*@dev",
+        "cakephp/console": "5.4.*@dev",
+        "cakephp/orm": "5.4.*@dev",
+        "cakephp/i18n": "5.4.*@dev",
         "paragonie/csp-builder": "^3.0"
     },
     "autoload": {
@@ -54,7 +56,8 @@
         "psr/http-client-implementation": "^1.0",
         "psr/http-factory-implementation": "^1.1",
         "psr/http-server-handler-implementation": "^1.0",
-        "psr/http-server-middleware-implementation": "^1.0"
+        "psr/http-server-middleware-implementation": "^1.0",
+        "psr/link-implementation": "^2.0"
     },
     "suggest": {
         "cakephp/cache": "To use cache session storage",
diff --git a/src/I18n/Number.php b/src/I18n/Number.php
index a264c871c5d..f06fbbc8924 100644
--- a/src/I18n/Number.php
+++ b/src/I18n/Number.php
@@ -69,6 +69,13 @@ class Number
      */
     protected static ?string $_defaultCurrencyFormat = null;
 
+    /**
+     * Default units used by Number::toReadableSize()
+     *
+     * @var bool
+     */
+    protected static bool $useIecUnits = false;
+
     /**
      * Formats a number with a level of precision.
      *
@@ -90,26 +97,51 @@ public static function precision(string|float|int $value, int $precision = 3, ar
     }
 
     /**
-     * Returns a formatted-for-humans file size.
+     * Returns a formatted-for-humans file size. By default, the units are exponents of ten (KB, MB, etc.).
+     * setUseIecUnits() can be used to swap to ISO/IEC 80000-13 units (KiB, MiB, etc).
+     * 1 KiB = 1024 Bytes
+     * 1 KB  = 1000 Bytes
      *
      * @param string|float|int $size Size in bytes
+     * @param bool|null $useIecUnits Whether to use exponent of two or ten for units (KiB, MiB, etc. or KB, MB, etc.)
      * @return string Human readable size
      * @link https://book.cakephp.org/5/en/core-libraries/number.html#interacting-with-human-readable-values
      */
-    public static function toReadableSize(string|float|int $size): string
+    public static function toReadableSize(string|float|int $size, ?bool $useIecUnits = null): string
     {
+        $useIec = $useIecUnits ?? static::$useIecUnits;
+
+        $units = $useIec
+        ? ['KiB', 'MiB', 'GiB', 'TiB']
+        : ['KB', 'MB', 'GB', 'TB'];
+
+        $divisor = $useIec ? 1024 : 1000;
+
         $size = (int)$size;
 
         return match (true) {
-            $size < 1024 => __dn('cake', '{0,number,integer} Byte', '{0,number,integer} Bytes', $size, $size),
-            round($size / 1024) < 1024 => __d('cake', '{0,number,#,###.##} KB', $size / 1024),
-            round($size / 1024 / 1024, 2) < 1024 => __d('cake', '{0,number,#,###.##} MB', $size / 1024 / 1024),
-            round($size / 1024 / 1024 / 1024, 2) < 1024 =>
-                __d('cake', '{0,number,#,###.##} GB', $size / 1024 / 1024 / 1024),
-            default => __d('cake', '{0,number,#,###.##} TB', $size / 1024 / 1024 / 1024 / 1024),
+            $size < $divisor => __dn('cake', '{0,number,integer} Byte', '{0,number,integer} Bytes', $size, $size),
+            round($size / $divisor) < $divisor => __d('cake', '{0,number,#,###.##} {1}', $size / $divisor, $units[0]),
+            round($size / pow($divisor, 2), 2) < $divisor =>
+            __d('cake', '{0,number,#,###.##} {1}', $size / pow($divisor, 2), $units[1]),
+            round($size / pow($divisor, 3), 2) < $divisor =>
+            __d('cake', '{0,number,#,###.##} {1}', $size / pow($divisor, 3), $units[2]),
+            default => __d('cake', '{0,number,#,###.##} {1}', $size / pow($divisor, 4), $units[3]),
         };
     }
 
+    /**
+     * Setter for units to use in toReadableSize(). If set to true, it will use IEC units, as defined in ISO/IEC 80000-13
+     * (KiB, MiB, etc.). Else it will use natural units (MB, KB, etc).
+     *
+     * @param bool $useIec Whether to use exponents of two or ten for units (KiB, MiB, etc. or KB, MB, etc.)  {@link toReadableSize()}
+     * @return void
+     */
+    public static function setUseIecUnits(bool $useIec): void
+    {
+        static::$useIecUnits = $useIec;
+    }
+
     /**
      * Formats a number into a percentage string.
      *
@@ -169,13 +201,18 @@ public static function format(string|float|int $value, array $options = []): str
      *
      * @param string $value A numeric string.
      * @param array<string, mixed> $options An array with options.
-     * @return float point number
+     * @return float|null Parsed float or null if parsing failed.
      */
-    public static function parseFloat(string $value, array $options = []): float
+    public static function parseFloat(string $value, array $options = []): ?float
     {
         $formatter = static::formatter($options);
+        $result = $formatter->parse($value, NumberFormatter::TYPE_DOUBLE);
+
+        if ($result === false) {
+            return null;
+        }
 
-        return (float)$formatter->parse($value, NumberFormatter::TYPE_DOUBLE);
+        return (float)$result;
     }
 
     /**
diff --git a/src/I18n/composer.json b/src/I18n/composer.json
index 16755c4af6f..dc66ed3f455 100644
--- a/src/I18n/composer.json
+++ b/src/I18n/composer.json
@@ -30,7 +30,7 @@
     "require": {
         "php": ">=8.2",
         "ext-intl": "*",
-        "cakephp/core": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
         "cakephp/chronos": "^3.3"
     },
     "autoload": {
diff --git a/src/Log/composer.json b/src/Log/composer.json
index a794a534254..f605732a31e 100644
--- a/src/Log/composer.json
+++ b/src/Log/composer.json
@@ -24,7 +24,7 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
         "psr/log": "^3.0"
     },
     "autoload": {
diff --git a/src/Mailer/Mailer.php b/src/Mailer/Mailer.php
index 3f4b32c6250..c4c96f5667a 100644
--- a/src/Mailer/Mailer.php
+++ b/src/Mailer/Mailer.php
@@ -140,6 +140,7 @@ class Mailer implements EventListenerInterface
      * Mailer's name.
      *
      * @var string
+     * @deprecated 5.4.0 This property is unused.
      */
     public static string $name;
 
diff --git a/src/ORM/Association/BelongsToMany.php b/src/ORM/Association/BelongsToMany.php
index d9fd2c9ab64..e6072495cf9 100644
--- a/src/ORM/Association/BelongsToMany.php
+++ b/src/ORM/Association/BelongsToMany.php
@@ -69,7 +69,7 @@ class BelongsToMany extends Association
      *
      * @var string
      */
-    protected string $_strategy = self::STRATEGY_SELECT;
+    protected string $_strategy = self::STRATEGY_SUBQUERY;
 
     /**
      * Junction table instance
diff --git a/src/ORM/Association/HasMany.php b/src/ORM/Association/HasMany.php
index 3b352b1dbf3..f12b4560d9a 100644
--- a/src/ORM/Association/HasMany.php
+++ b/src/ORM/Association/HasMany.php
@@ -59,7 +59,7 @@ class HasMany extends Association
      *
      * @var string
      */
-    protected string $_strategy = self::STRATEGY_SELECT;
+    protected string $_strategy = self::STRATEGY_SUBQUERY;
 
     /**
      * Valid strategies for this type of association
diff --git a/src/ORM/Association/Loader/SelectLoader.php b/src/ORM/Association/Loader/SelectLoader.php
index 866e6ac7fbd..012a33fbc7a 100644
--- a/src/ORM/Association/Loader/SelectLoader.php
+++ b/src/ORM/Association/Loader/SelectLoader.php
@@ -17,7 +17,9 @@
 namespace Cake\ORM\Association\Loader;
 
 use Cake\Database\Exception\DatabaseException;
+use Cake\Database\Expression\AggregateExpression;
 use Cake\Database\Expression\IdentifierExpression;
+use Cake\Database\Expression\QueryExpression;
 use Cake\Database\Expression\TupleComparison;
 use Cake\Database\ExpressionInterface;
 use Cake\Database\ValueBinder;
@@ -444,6 +446,10 @@ protected function _buildSubquery(SelectQuery $query): SelectQuery
      * those columns are also included as the fields may be calculated or constant values,
      * that need to be present to ensure the correct association data is loaded.
      *
+     * When a HAVING clause is present the original SELECT aliases are preserved as
+     * well, since HAVING may reference computed aliases that would otherwise be
+     * dropped from the reduced subquery SELECT list.
+     *
      * @param \Cake\ORM\Query\SelectQuery<\Cake\Datasource\EntityInterface|array> $query The query to get fields from.
      * @return array<string, array> The list of fields for the subquery.
      */
@@ -459,10 +465,11 @@ protected function _subqueryFields(SelectQuery $query): array
         $group = array_values($fields);
         $fields = $group;
 
-        /** @var \Cake\Database\Expression\QueryExpression $order */
+        $columns = $query->clause('select');
+
+        /** @var \Cake\Database\Expression\QueryExpression|null $order */
         $order = $query->clause('order');
         if ($order) {
-            $columns = $query->clause('select');
             $order->iterateParts(function ($direction, $field) use (&$fields, $columns): void {
                 if (isset($columns[$field])) {
                     $fields[$field] = $columns[$field];
@@ -470,6 +477,41 @@ protected function _subqueryFields(SelectQuery $query): array
             });
         }
 
+        $having = $query->clause('having');
+        if ($having instanceof QueryExpression && $having->count() > 0) {
+            $reserved = [];
+            foreach ($keys as $k) {
+                $reserved[strtolower(trim((string)$k, '`"[]'))] = true;
+            }
+
+            $havingSql = $having->sql(new ValueBinder());
+            foreach ($columns as $alias => $column) {
+                if (!is_string($alias) || isset($fields[$alias])) {
+                    continue;
+                }
+                $cleanAlias = trim($alias, '`"[]');
+                if (isset($reserved[strtolower($cleanAlias)])) {
+                    continue;
+                }
+                if (preg_match('/\b' . preg_quote($cleanAlias, '/') . '\b/', $havingSql) !== 1) {
+                    continue;
+                }
+                $fields[$alias] = $column;
+
+                $isAggregate = $column instanceof AggregateExpression;
+                if (!$isAggregate && $column instanceof ExpressionInterface) {
+                    $column->traverse(function ($sub) use (&$isAggregate): void {
+                        if ($sub instanceof AggregateExpression) {
+                            $isAggregate = true;
+                        }
+                    });
+                }
+                if (!$isAggregate) {
+                    $group[] = $column;
+                }
+            }
+        }
+
         return ['select' => $fields, 'group' => $group];
     }
 
diff --git a/src/ORM/AssociationsNormalizerTrait.php b/src/ORM/AssociationsNormalizerTrait.php
index 6f869d2196a..a85c5549758 100644
--- a/src/ORM/AssociationsNormalizerTrait.php
+++ b/src/ORM/AssociationsNormalizerTrait.php
@@ -24,7 +24,12 @@ trait AssociationsNormalizerTrait
 {
     /**
      * Returns an array out of the original passed associations list where dot notation
-     * is transformed into nested arrays so that they can be parsed by other routines
+     * is transformed into nested arrays so that they can be parsed by other routines.
+     *
+     * This method now supports the same nested array format as contain(), allowing:
+     * - Dot notation: ['First.Second']
+     * - Nested arrays: ['First' => ['Second', 'Third']]
+     * - Mixed with options: ['First' => ['Second', 'onlyIds' => true]]
      *
      * @param array|string $associations The array of included associations.
      * @return array An array having dot notation transformed into nested arrays
@@ -40,6 +45,16 @@ protected function _normalizeAssociations(array|string $associations): array
                 $options = [];
             }
 
+            // Handle nested array format like contain()
+            // Only transform if the array looks like it contains associations (not just a simple array value)
+            if (is_array($options) && !isset($options['associated']) && $this->_shouldExtractAssociations($options)) {
+                [$nestedAssociations, $actualOptions] = $this->_extractAssociations($options);
+                if ($nestedAssociations) {
+                    $actualOptions['associated'] = $this->_normalizeAssociations($nestedAssociations);
+                }
+                $options = $actualOptions;
+            }
+
             if (!str_contains($table, '.')) {
                 $result[$table] = $options;
                 continue;
@@ -67,4 +82,95 @@ protected function _normalizeAssociations(array|string $associations): array
 
         return $result['associated'] ?? $result;
     }
+
+    /**
+     * Determines if an array should have associations extracted from it.
+     *
+     * Returns true if the array appears to be mixing association names with options,
+     * or if it contains nested association structures (like contain() format).
+     * Returns false for simple arrays that should be kept as-is.
+     *
+     * Uses CakePHP naming conventions to detect associations vs options:
+     * - Association names start with uppercase (CamelCase): Users, Articles
+     * - Option keys start with lowercase (camelCase): onlyIds, conditions
+     * - Special data keys start with underscore: _joinData, _ids
+     *
+     * @param array $options The options array to check.
+     * @return bool
+     */
+    protected function _shouldExtractAssociations(array $options): bool
+    {
+        // Empty arrays should not be transformed
+        if (!$options) {
+            return false;
+        }
+
+        $hasOptionKey = false;
+        $hasStringKeys = false;
+        $hasNestedArrayValues = false;
+        $hasMultipleItems = count($options) > 1;
+
+        foreach ($options as $key => $value) {
+            if (is_string($key)) {
+                $hasStringKeys = true;
+                // Option keys start with lowercase letter (camelCase convention)
+                if (preg_match('/^[a-z]/', $key)) {
+                    $hasOptionKey = true;
+                }
+            }
+            // Check if value is an array (potential nested association)
+            if (is_array($value)) {
+                $hasNestedArrayValues = true;
+            }
+        }
+
+        // Only extract associations if:
+        // 1. We have an option key (mixing associations and options)
+        // 2. We have string keys AND nested array values (contain-like format with nested associations)
+        // 3. We have multiple items (likely a list of associations like ['Users', 'Comments'])
+        return $hasOptionKey || ($hasStringKeys && $hasNestedArrayValues) || $hasMultipleItems;
+    }
+
+    /**
+     * Extracts association names from options array, separating them from actual options.
+     *
+     * Uses CakePHP naming conventions to distinguish associations from options:
+     * - Association names start with uppercase (CamelCase): Users, Articles
+     * - Special data keys start with underscore: _joinData, _ids (treated as associations)
+     * - Option keys start with lowercase (camelCase): onlyIds, conditions
+     *
+     * This allows the same nested array format as contain():
+     * - ['Users', 'Comments'] → associations
+     * - ['Users' => [...], 'Comments'] → associations
+     * - ['onlyIds' => true, 'validate' => false] → options only
+     * - ['Users', 'onlyIds' => true] → mixed
+     *
+     * @param array $options The options array that may contain nested associations.
+     * @return array An array with two elements: [associations, options]
+     */
+    protected function _extractAssociations(array $options): array
+    {
+        $associations = [];
+        $actualOptions = [];
+
+        foreach ($options as $key => $value) {
+            // Numeric keys are always association names (string values like 'Users')
+            if (is_int($key)) {
+                $associations[] = $value;
+                continue;
+            }
+
+            // String keys starting with uppercase or underscore are associations/data keys
+            // This follows CakePHP conventions: CamelCase for models, _prefix for special data
+            if (preg_match('/^[A-Z_]/', $key)) {
+                $associations[$key] = $value;
+                continue;
+            }
+
+            // Everything else (lowercase start) is an option key
+            $actualOptions[$key] = $value;
+        }
+
+        return [$associations, $actualOptions];
+    }
 }
diff --git a/src/ORM/Attribute/CollectionOf.php b/src/ORM/Attribute/CollectionOf.php
index 7c60dbff5df..418d025ad85 100644
--- a/src/ORM/Attribute/CollectionOf.php
+++ b/src/ORM/Attribute/CollectionOf.php
@@ -38,13 +38,13 @@
  * ```
  */
 #[Attribute(Attribute::TARGET_PARAMETER | Attribute::TARGET_PROPERTY)]
-class CollectionOf
+readonly class CollectionOf
 {
     /**
      * @param class-string $class The DTO class for collection elements
      */
     public function __construct(
-        public string $class,
+        protected string $class,
     ) {
     }
 }
diff --git a/src/ORM/Table.php b/src/ORM/Table.php
index 9e9f02dd887..7a22e52d26c 100644
--- a/src/ORM/Table.php
+++ b/src/ORM/Table.php
@@ -127,14 +127,20 @@
  * - `Model.afterSaveCommit` Fired after the transaction in which the save operation is
  *   wrapped has been committed. It’s also triggered for non atomic saves where database
  *   operations are implicitly committed. The event is triggered only for the primary
- *   table on which save() is directly called. The event is not triggered if a
- *   transaction is started before calling save.
+ *   table on which save() is directly called. When called inside an outer transaction,
+ *   the event is deferred until the outermost transaction commits.
  *
  * - `Model.beforeDelete` Fired before an entity is deleted. By stopping this
  *   event you will abort the delete operation.
  *
  * - `Model.afterDelete` Fired after an entity has been deleted.
  *
+ * - `Model.afterDeleteCommit` Fired after the transaction in which the delete operation is
+ *   wrapped has been committed. It's also triggered for non atomic deletes where database
+ *   operations are implicitly committed. The event is triggered only for the primary
+ *   table on which delete() is directly called. When called inside an outer transaction,
+ *   the event is deferred until the outermost transaction commits.
+ *
  * ### Callbacks
  *
  * You can subscribe to the events listed above in your table classes by implementing the
@@ -1658,6 +1664,13 @@ public function findOrCreate(
 
         if ($entity && $this->_transactionCommitted($options['atomic'], true)) {
             $this->dispatchEvent('Model.afterSaveCommit', compact('entity', 'options'));
+        } elseif ($entity && $this->getConnection()->inTransaction()) {
+            $this->getConnection()->afterCommit(
+                fn() => $this->dispatchEvent('Model.afterSaveCommit', [
+                    'entity' => $entity,
+                    'options' => $options,
+                ]),
+            );
         }
 
         return $entity;
@@ -1976,15 +1989,35 @@ public function save(
         );
 
         if ($success) {
+            $deferToCommit = $options['_primary']
+                && $this->getConnection()->inTransaction();
+
             if ($this->_transactionCommitted($options['atomic'], $options['_primary'])) {
                 $this->dispatchEvent('Model.afterSaveCommit', compact('entity', 'options'));
+            } elseif ($deferToCommit) {
+                $this->getConnection()->afterCommit(
+                    fn() => $this->dispatchEvent('Model.afterSaveCommit', [
+                        'entity' => $entity,
+                        'options' => $options,
+                    ]),
+                );
             }
             if ($options['atomic'] || $options['_primary']) {
-                if ($options['_cleanOnSuccess']) {
-                    $entity->clean();
-                    $entity->setNew(false);
+                if ($deferToCommit) {
+                    $this->getConnection()->afterCommit(function () use ($entity, $options): void {
+                        if ($options['_cleanOnSuccess']) {
+                            $entity->clean();
+                            $entity->setNew(false);
+                        }
+                        $entity->setSource($this->getRegistryAlias());
+                    });
+                } else {
+                    if ($options['_cleanOnSuccess']) {
+                        $entity->clean();
+                        $entity->setNew(false);
+                    }
+                    $entity->setSource($this->getRegistryAlias());
                 }
-                $entity->setSource($this->getRegistryAlias());
             }
         }
 
@@ -2399,9 +2432,9 @@ protected function _saveMany(
             }
         };
 
+        // afterSaveCommit is dispatched by individual save() calls via afterCommit()
         if ($this->_transactionCommitted($options['atomic'], $options['_primary'])) {
             foreach ($entities as $entity) {
-                $this->dispatchEvent('Model.afterSaveCommit', compact('entity', 'options'));
                 if ($options['atomic'] || $options['_primary']) {
                     $cleanupOnSuccess($entity);
                 }
@@ -2459,6 +2492,13 @@ public function delete(EntityInterface $entity, array $options = []): bool
                 'entity' => $entity,
                 'options' => $options,
             ]);
+        } elseif ($success && $options['_primary'] && $this->getConnection()->inTransaction()) {
+            $this->getConnection()->afterCommit(
+                fn() => $this->dispatchEvent('Model.afterDeleteCommit', [
+                    'entity' => $entity,
+                    'options' => $options,
+                ]),
+            );
         }
 
         return $success;
@@ -2544,6 +2584,15 @@ protected function _deleteMany(iterable $entities, array $options = []): ?Entity
                     'options' => $options,
                 ]);
             }
+        } elseif ($failed === null && $options['_primary'] && $this->getConnection()->inTransaction()) {
+            foreach ($entities as $entity) {
+                $this->getConnection()->afterCommit(
+                    fn() => $this->dispatchEvent('Model.afterDeleteCommit', [
+                        'entity' => $entity,
+                        'options' => $options,
+                    ]),
+                );
+            }
         }
 
         return $failed;
diff --git a/src/ORM/composer.json b/src/ORM/composer.json
index 7e70501870b..59682698cb9 100644
--- a/src/ORM/composer.json
+++ b/src/ORM/composer.json
@@ -24,17 +24,17 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/collection": "^5.3.0",
-        "cakephp/core": "^5.3.0",
-        "cakephp/datasource": "^5.3.0",
-        "cakephp/database": "^5.3.0",
-        "cakephp/event": "^5.3.0",
-        "cakephp/utility": "^5.3.0",
-        "cakephp/validation": "^5.3.0"
+        "cakephp/collection": "5.4.*@dev",
+        "cakephp/core": "5.4.*@dev",
+        "cakephp/datasource": "5.4.*@dev",
+        "cakephp/database": "5.4.*@dev",
+        "cakephp/event": "5.4.*@dev",
+        "cakephp/utility": "5.4.*@dev",
+        "cakephp/validation": "5.4.*@dev"
     },
     "require-dev": {
-        "cakephp/cache": "^5.3.0",
-        "cakephp/i18n": "^5.3.0"
+        "cakephp/cache": "5.4.*@dev",
+        "cakephp/i18n": "5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/TestSuite/TestCase.php b/src/TestSuite/TestCase.php
index 368db63f82b..2ff08b47ab5 100644
--- a/src/TestSuite/TestCase.php
+++ b/src/TestSuite/TestCase.php
@@ -39,6 +39,7 @@
 use Exception;
 use LogicException;
 use Mockery;
+use Mockery\LegacyMockInterface;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase as BaseTestCase;
 use ReflectionClass;
@@ -1035,7 +1036,7 @@ protected function skipUnless($condition, $message = '')
 // phpcs:enable
 
     /**
-     * Mock a model, maintain fixtures and table association
+     * Mock a model with PHPUnit mocks, maintain fixtures and table association
      *
      * @param string $alias The model to get a mock for.
      * @param array<string> $methods The list of methods to mock
@@ -1105,6 +1106,48 @@ public function getMockForModel(string $alias, array $methods = [], array $optio
         return $mock;
     }
 
+    /**
+     * Mock a model with Mockery mocks, maintain fixtures and table association
+     *
+     * @template T of \Cake\ORM\Table
+     * @param string|class-string<T> $alias The alias or the FQCN of the model to get a mock for.
+     * @param array<string, mixed> $options The config data for the mock's constructor.
+     * @return (T|\Cake\ORM\Table)&\Mockery\LegacyMockInterface
+     */
+    public function mockModel(string $alias, array $options = []): Table&LegacyMockInterface
+    {
+        $className = $this->_getTableClassName($alias, $options);
+        $connectionName = $className::defaultConnectionName();
+        $connection = ConnectionManager::get($connectionName);
+
+        $locator = $this->getTableLocator();
+
+        [, $baseClass] = pluginSplit($alias);
+        $options += ['alias' => $baseClass, 'connection' => $connection];
+        $options += $locator->getConfig($alias);
+
+        $mock = Mockery::mock(new $className($options))->makePartial();
+        assert($mock instanceof Table);
+
+        if (empty($options['entityClass']) && $mock->getEntityClass() === Entity::class) {
+            $parts = explode('\\', $className);
+            $entityAlias = Inflector::classify(Inflector::underscore(substr(array_pop($parts), 0, -5)));
+            $entityClass = implode('\\', array_slice($parts, 0, -1)) . '\\Entity\\' . $entityAlias;
+            if (class_exists($entityClass)) {
+                $mock->setEntityClass($entityClass);
+            }
+        }
+
+        if (stripos($mock->getTable(), 'mock') === 0) {
+            $mock->setTable(Inflector::tableize($baseClass));
+        }
+
+        $locator->set($baseClass, $mock);
+        $locator->set($alias, $mock);
+
+        return $mock;
+    }
+
     /**
      * Gets the class name for the table.
      *
diff --git a/src/Utility/Filesystem.php b/src/Utility/Filesystem.php
index 31743161bb9..e53a978a29e 100644
--- a/src/Utility/Filesystem.php
+++ b/src/Utility/Filesystem.php
@@ -17,11 +17,11 @@
 namespace Cake\Utility;
 
 use Cake\Core\Exception\CakeException;
+use Cake\Utility\Fs\Iterator\HiddenFileFilterIterator;
 use CallbackFilterIterator;
 use Closure;
 use FilesystemIterator;
 use Iterator;
-use RecursiveCallbackFilterIterator;
 use RecursiveDirectoryIterator;
 use RecursiveIteratorIterator;
 use RegexIterator;
@@ -58,13 +58,19 @@ public function find(string $path, Closure|string|null $filter = null, ?int $fla
         $flags ??= FilesystemIterator::KEY_AS_PATHNAME
             | FilesystemIterator::CURRENT_AS_FILEINFO
             | FilesystemIterator::SKIP_DOTS;
+
         $directory = new FilesystemIterator($path, $flags);
 
+        // Apply filter if provided
         if ($filter === null) {
             return $directory;
         }
 
-        return $this->filterIterator($directory, $filter);
+        if (is_string($filter)) {
+            return new RegexIterator($directory, $filter);
+        }
+
+        return new CallbackFilterIterator($directory, $filter);
     }
 
     /**
@@ -82,40 +88,19 @@ public function findRecursive(string $path, Closure|string|null $filter = null,
         $flags ??= FilesystemIterator::KEY_AS_PATHNAME
             | FilesystemIterator::CURRENT_AS_FILEINFO
             | FilesystemIterator::SKIP_DOTS;
-        $directory = new RecursiveDirectoryIterator($path, $flags);
 
-        $dirFilter = new RecursiveCallbackFilterIterator(
-            $directory,
-            function (SplFileInfo $current) {
-                if (str_starts_with($current->getFilename(), '.') && $current->isDir()) {
-                    return false;
-                }
+        $directory = new RecursiveDirectoryIterator($path, $flags);
 
-                return true;
-            },
-        );
+        // Filter out hidden directories
+        $filtered = new HiddenFileFilterIterator($directory);
 
-        $flatten = new RecursiveIteratorIterator(
-            $dirFilter,
-            RecursiveIteratorIterator::CHILD_FIRST,
-        );
+        $iterator = new RecursiveIteratorIterator($filtered, RecursiveIteratorIterator::CHILD_FIRST);
 
+        // Apply custom filter if provided
         if ($filter === null) {
-            return $flatten;
+            return $iterator;
         }
 
-        return $this->filterIterator($flatten, $filter);
-    }
-
-    /**
-     * Wrap iterator in additional filtering iterator.
-     *
-     * @param \Iterator $iterator Iterator
-     * @param \Closure|string $filter Regex string or callback.
-     * @return \Iterator
-     */
-    protected function filterIterator(Iterator $iterator, Closure|string $filter): Iterator
-    {
         if (is_string($filter)) {
             return new RegexIterator($iterator, $filter);
         }
diff --git a/src/Utility/Fs/Enum/DepthOperator.php b/src/Utility/Fs/Enum/DepthOperator.php
new file mode 100644
index 00000000000..7c2addbae82
--- /dev/null
+++ b/src/Utility/Fs/Enum/DepthOperator.php
@@ -0,0 +1,55 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Enum;
+
+/**
+ * Enum for depth comparison operators
+ *
+ * Defines the comparison operators that can be used with Finder::depth()
+ */
+enum DepthOperator: string
+{
+    /**
+     * Equal to (==)
+     */
+    case EQUAL = '==';
+
+    /**
+     * Not equal to (!=)
+     */
+    case NOT_EQUAL = '!=';
+
+    /**
+     * Less than (<)
+     */
+    case LESS_THAN = '<';
+
+    /**
+     * Greater than (>)
+     */
+    case GREATER_THAN = '>';
+
+    /**
+     * Less than or equal to (<=)
+     */
+    case LESS_THAN_OR_EQUAL = '<=';
+
+    /**
+     * Greater than or equal to (>=)
+     */
+    case GREATER_THAN_OR_EQUAL = '>=';
+}
diff --git a/src/Utility/Fs/Enum/FinderMode.php b/src/Utility/Fs/Enum/FinderMode.php
new file mode 100644
index 00000000000..1fbf5a9b7fc
--- /dev/null
+++ b/src/Utility/Fs/Enum/FinderMode.php
@@ -0,0 +1,40 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Enum;
+
+/**
+ * Enum for Finder iteration modes
+ *
+ * Defines what type of filesystem items to iterate over.
+ */
+enum FinderMode
+{
+    /**
+     * Iterate only files
+     */
+    case FILES;
+
+    /**
+     * Iterate only directories
+     */
+    case DIRECTORIES;
+
+    /**
+     * Iterate both files and directories
+     */
+    case ALL;
+}
diff --git a/src/Utility/Fs/Finder.php b/src/Utility/Fs/Finder.php
new file mode 100644
index 00000000000..7bab0abc501
--- /dev/null
+++ b/src/Utility/Fs/Finder.php
@@ -0,0 +1,436 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs;
+
+use AppendIterator;
+use Cake\Utility\Fs\Enum\DepthOperator;
+use Cake\Utility\Fs\Enum\FinderMode;
+use Cake\Utility\Fs\Iterator\CallbackFilterIterator;
+use Cake\Utility\Fs\Iterator\ContainsPathFilterIterator;
+use Cake\Utility\Fs\Iterator\DepthFilterIterator;
+use Cake\Utility\Fs\Iterator\ExcludeDirectoryFilterIterator;
+use Cake\Utility\Fs\Iterator\FilenameFilterIterator;
+use Cake\Utility\Fs\Iterator\FileTypeFilterIterator;
+use Cake\Utility\Fs\Iterator\GlobFilterIterator;
+use Cake\Utility\Fs\Iterator\HiddenFileFilterIterator;
+use Closure;
+use FilesystemIterator;
+use Iterator;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
+
+/**
+ * Finder provides a fluent interface for finding files and directories.
+ *
+ * Example usage:
+ * ```php
+ * // Find files
+ * $finder = new Finder();
+ * $files = $finder
+ *     ->in('src')
+ *     ->name('*.php')
+ *     ->exclude('vendor')
+ *     ->files();
+ *
+ * foreach ($files as $file) {
+ *     echo $file->getPathname();
+ * }
+ *
+ * // Find directories
+ * $directories = (new Finder())
+ *     ->in('src')
+ *     ->exclude('vendor')
+ *     ->directories();
+ *
+ * // Find both files and directories
+ * $all = (new Finder())
+ *     ->in('src')
+ *     ->all();
+ * ```
+ */
+class Finder
+{
+    /**
+     * Base paths to search in
+     *
+     * @var array<string>
+     */
+    protected array $paths = [];
+
+    /**
+     * Name patterns to match
+     *
+     * @var array<string>
+     */
+    protected array $names = [];
+
+    /**
+     * Name patterns to exclude
+     *
+     * @var array<string>
+     */
+    protected array $notNames = [];
+
+    /**
+     * Directories to exclude
+     *
+     * @var array<string>
+     */
+    protected array $exclude = [];
+
+    /**
+     * Path patterns to include
+     *
+     * @var array<string>
+     */
+    protected array $pathPatterns = [];
+
+    /**
+     * Path patterns to exclude
+     *
+     * @var array<string>
+     */
+    protected array $notPathPatterns = [];
+
+    /**
+     * Glob patterns for full path matching
+     *
+     * @var array<string>
+     */
+    protected array $globPatterns = [];
+
+    /**
+     * Depth conditions
+     *
+     * @var array<array{0: \Cake\Utility\Fs\Enum\DepthOperator, 1: int}>
+     */
+    protected array $depths = [];
+
+    /**
+     * Whether to ignore hidden files
+     *
+     * @var bool
+     */
+    protected bool $ignoreHiddenFiles = true;
+
+    /**
+     * Whether to search recursively
+     *
+     * @var bool
+     */
+    protected bool $recursive = true;
+
+    /**
+     * The iteration mode (files, directories, or all)
+     *
+     * @var \Cake\Utility\Fs\Enum\FinderMode|null
+     */
+    protected ?FinderMode $mode = null;
+
+    /**
+     * Custom filter callbacks
+     *
+     * @var array<\Closure(\SplFileInfo, string): bool>
+     */
+    protected array $filters = [];
+
+    /**
+     * Add a path to search in.
+     *
+     * @param string $path The directory path
+     * @return $this
+     */
+    public function in(string $path)
+    {
+        $this->paths[] = $path;
+
+        return $this;
+    }
+
+    /**
+     * Add a name pattern to match.
+     *
+     * @param string $pattern Glob pattern (e.g., '*.php')
+     * @return $this
+     */
+    public function name(string $pattern)
+    {
+        $this->names[] = $pattern;
+
+        return $this;
+    }
+
+    /**
+     * Add a name pattern that must not be matched.
+     *
+     * @param string $pattern Glob pattern to exclude (e.g., '*.rb', '*Test.php')
+     * @return $this
+     */
+    public function notName(string $pattern)
+    {
+        $this->notNames[] = $pattern;
+
+        return $this;
+    }
+
+    /**
+     * Exclude a directory from the search.
+     *
+     * @param string $directory Directory name to exclude
+     * @return $this
+     */
+    public function exclude(string $directory)
+    {
+        $this->exclude[] = $directory;
+
+        return $this;
+    }
+
+    /**
+     * Add a path pattern that must be matched.
+     *
+     * @param string $pattern Path pattern (e.g., 'Controller')
+     * @return $this
+     */
+    public function path(string $pattern)
+    {
+        $this->pathPatterns[] = $pattern;
+
+        return $this;
+    }
+
+    /**
+     * Add a path pattern that must not be matched.
+     *
+     * @param string $pattern Path pattern to exclude
+     * @return $this
+     */
+    public function notPath(string $pattern)
+    {
+        $this->notPathPatterns[] = $pattern;
+
+        return $this;
+    }
+
+    /**
+     * Add a glob pattern for full path matching.
+     *
+     * Supports wildcards like `src/**\/*.php` for recursive matching.
+     *
+     * @param string $pattern Glob pattern (e.g., 'src/**\/*.php', 'tests/**\/*Test.php')
+     * @return $this
+     */
+    public function pattern(string $pattern)
+    {
+        $this->globPatterns[] = $pattern;
+
+        return $this;
+    }
+
+    /**
+     * Add a custom filter callback.
+     *
+     * The callback receives the SplFileInfo object and relative path,
+     * and should return true to include the file.
+     *
+     * Example:
+     * ```php
+     * $finder->filter(fn(\SplFileInfo $file) => $file->getSize() > 1024);
+     * ```
+     *
+     * @param \Closure(\SplFileInfo, string): bool $callback Filter callback
+     * @return $this
+     */
+    public function filter(Closure $callback)
+    {
+        $this->filters[] = $callback;
+
+        return $this;
+    }
+
+    /**
+     * Add a depth condition.
+     *
+     * @param int $level The depth level (0 = top-level directory)
+     * @param \Cake\Utility\Fs\Enum\DepthOperator $operator The comparison operator (default: EQUAL)
+     * @return $this
+     */
+    public function depth(int $level, DepthOperator $operator = DepthOperator::EQUAL)
+    {
+        $this->depths[] = [$operator, $level];
+
+        return $this;
+    }
+
+    /**
+     * Set whether to ignore hidden files and directories.
+     *
+     * @param bool $ignore Whether to ignore hidden files
+     * @return $this
+     */
+    public function ignoreHiddenFiles(bool $ignore = true)
+    {
+        $this->ignoreHiddenFiles = $ignore;
+
+        return $this;
+    }
+
+    /** Set whether to search recursively into subdirectories.
+     *
+     * @param bool $recursive Whether to search recursively (default: true)
+     * @return $this
+     */
+    public function recursive(bool $recursive = true)
+    {
+        $this->recursive = $recursive;
+
+        return $this;
+    }
+
+    /**
+     * Get files matching the criteria.
+     *
+     * @return \Iterator<\SplFileInfo>
+     */
+    public function files(): Iterator
+    {
+        $this->mode = FinderMode::FILES;
+
+        return $this->iterate();
+    }
+
+    /**
+     * Get directories matching the criteria.
+     *
+     * @return \Iterator<\SplFileInfo>
+     */
+    public function directories(): Iterator
+    {
+        $this->mode = FinderMode::DIRECTORIES;
+
+        return $this->iterate();
+    }
+
+    /**
+     * Get both files and directories matching the criteria.
+     *
+     * @return \Iterator<\SplFileInfo>
+     */
+    public function all(): Iterator
+    {
+        $this->mode = FinderMode::ALL;
+
+        return $this->iterate();
+    }
+
+    /**
+     * Iterate over items matching the criteria.
+     *
+     * @return \Iterator<\SplFileInfo>
+     */
+    protected function iterate(): Iterator
+    {
+        // Combine results from all paths
+        if (count($this->paths) === 1) {
+            return $this->buildIterator($this->paths[0]);
+        }
+
+        // Multiple paths - use AppendIterator
+        $append = new AppendIterator();
+        foreach ($this->paths as $path) {
+            $append->append($this->buildIterator($path));
+        }
+
+        return $append;
+    }
+
+    /**
+     * Build an iterator chain with all configured filters.
+     *
+     * @param string $path The directory path
+     * @return \Iterator<\SplFileInfo>
+     */
+    protected function buildIterator(string $path): Iterator
+    {
+        $flags = FilesystemIterator::KEY_AS_PATHNAME
+            | FilesystemIterator::CURRENT_AS_FILEINFO
+            | FilesystemIterator::SKIP_DOTS;
+
+        $directory = new RecursiveDirectoryIterator($path, $flags);
+
+        // Apply hidden file filtering
+        if ($this->ignoreHiddenFiles) {
+            $directory = new HiddenFileFilterIterator($directory);
+        }
+
+        // Apply directory exclusions
+        if ($this->exclude !== []) {
+            $directory = new ExcludeDirectoryFilterIterator($directory, $this->exclude);
+        }
+
+        // Apply path pattern exclusions during recursion
+        if ($this->notPathPatterns !== []) {
+            $directory = new ContainsPathFilterIterator($directory, $this->notPathPatterns, negate: true);
+        }
+
+        // Apply path pattern inclusions during recursion (non-regex patterns only)
+        if ($this->pathPatterns !== []) {
+            $directory = new ContainsPathFilterIterator($directory, $this->pathPatterns);
+        }
+
+        // Use SELF_FIRST when looking for directories to include them in iteration
+        // Use LEAVES_ONLY when looking for files only for optimization
+        $iteratorMode = $this->mode === FinderMode::FILES
+            ? RecursiveIteratorIterator::LEAVES_ONLY
+            : RecursiveIteratorIterator::SELF_FIRST;
+
+        $iterator = new RecursiveIteratorIterator($directory, $iteratorMode);
+
+        // Apply file type filtering
+        if ($this->mode !== null && $this->mode !== FinderMode::ALL) {
+            $iterator = new FileTypeFilterIterator($iterator, $this->mode);
+        }
+
+        // Apply filename filtering
+        if ($this->names !== []) {
+            $iterator = new FilenameFilterIterator($iterator, $this->names);
+        }
+        if ($this->notNames !== []) {
+            $iterator = new FilenameFilterIterator($iterator, $this->notNames, negate: true);
+        }
+
+        // Apply depth filtering (handles non-recursive mode when recursive=false)
+        if (!$this->recursive) {
+            $iterator = new DepthFilterIterator($iterator, DepthOperator::EQUAL, 0);
+        }
+        foreach ($this->depths as [$operator, $level]) {
+            $iterator = new DepthFilterIterator($iterator, $operator, $level);
+        }
+
+        // Apply glob pattern filtering
+        if ($this->globPatterns !== []) {
+            $iterator = new GlobFilterIterator($iterator, $this->globPatterns, $path);
+        }
+
+        // Apply custom filters
+        foreach ($this->filters as $callback) {
+            $iterator = new CallbackFilterIterator($iterator, $callback, $path);
+        }
+
+        return $iterator;
+    }
+}
diff --git a/src/Utility/Fs/Iterator/CallbackFilterIterator.php b/src/Utility/Fs/Iterator/CallbackFilterIterator.php
new file mode 100644
index 00000000000..f9a7a6889d7
--- /dev/null
+++ b/src/Utility/Fs/Iterator/CallbackFilterIterator.php
@@ -0,0 +1,60 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use Cake\Utility\Fs\Path;
+use Closure;
+use FilterIterator;
+use Iterator;
+
+/**
+ * Filters files using a custom callback function.
+ *
+ * @extends \FilterIterator<string, \SplFileInfo, \Iterator<string, \SplFileInfo>>
+ */
+final class CallbackFilterIterator extends FilterIterator
+{
+    /**
+     * @param \Iterator $iterator The iterator to filter
+     * @param \Closure(\SplFileInfo, string): bool $callback Filter callback
+     * @param string $basePath Base path for calculating relative paths
+     */
+    public function __construct(
+        Iterator $iterator,
+        protected Closure $callback,
+        protected readonly string $basePath,
+    ) {
+        parent::__construct($iterator);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        /** @var \SplFileInfo $file */
+        $file = $this->current();
+
+        // Calculate relative path
+        $relativePath = Path::makeRelative(
+            Path::normalize($file->getPathname()),
+            Path::normalize($this->basePath),
+        );
+
+        return ($this->callback)($file, $relativePath);
+    }
+}
diff --git a/src/Utility/Fs/Iterator/ContainsPathFilterIterator.php b/src/Utility/Fs/Iterator/ContainsPathFilterIterator.php
new file mode 100644
index 00000000000..2c89004aac5
--- /dev/null
+++ b/src/Utility/Fs/Iterator/ContainsPathFilterIterator.php
@@ -0,0 +1,139 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use Cake\Utility\Fs\Path;
+use RecursiveFilterIterator;
+use RecursiveIterator;
+
+/**
+ * Filters files based on whether their path contains or matches specific patterns.
+ *
+ * Supports two types of patterns:
+ * - String patterns: Uses substring matching (str_contains) for simple strings
+ * - Regex patterns: Uses preg_match for patterns starting with /, #, or ~
+ *
+ * Uses OR logic: accepts if any pattern matches.
+ * Always allows directories to enable recursive traversal.
+ *
+ * Can be used to include or exclude files based on the $negate parameter:
+ * - When $negate is false (default): includes files matching patterns
+ * - When $negate is true: excludes files matching patterns
+ */
+final class ContainsPathFilterIterator extends RecursiveFilterIterator
+{
+    /**
+     * String patterns (substring matching, normalized)
+     *
+     * @var array<string>
+     */
+    protected array $stringPatterns;
+
+    /**
+     * Regex patterns (pattern matching, normalized)
+     *
+     * @var array<string>
+     */
+    protected array $regexPatterns;
+
+    /**
+     * @param \RecursiveIterator<string, \SplFileInfo> $iterator The iterator to filter
+     * @param array<string> $patterns Path patterns to match (string or regex)
+     * @param bool $negate When true, inverts the filter (excludes matching paths)
+     */
+    public function __construct(
+        RecursiveIterator $iterator,
+        array $patterns,
+        protected readonly bool $negate = false,
+    ) {
+        parent::__construct($iterator);
+
+        // Separate regex patterns from string patterns
+        $regexPatterns = [];
+        $stringPatterns = [];
+
+        foreach ($patterns as $pattern) {
+            if (preg_match('/^[\/#~]/', $pattern)) {
+                $regexPatterns[] = $pattern;
+            } else {
+                $stringPatterns[] = $pattern;
+            }
+        }
+
+        // Normalize string patterns for cross-platform compatibility
+        $this->stringPatterns = array_map(fn(string $p) => Path::normalize($p), $stringPatterns);
+
+        // Normalize regex patterns (normalize the paths they'll match against)
+        $this->regexPatterns = $regexPatterns;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        $current = $this->current();
+
+        // Always accept directories to allow traversal
+        if ($current->isDir()) {
+            return true;
+        }
+
+        // If no patterns at all, accept everything (no-op)
+        if ($this->stringPatterns === [] && $this->regexPatterns === []) {
+            return true;
+        }
+
+        // For files, check if path matches patterns
+        $path = Path::normalize($current->getPathname());
+        $matches = false;
+
+        // Check string patterns (substring matching)
+        foreach ($this->stringPatterns as $pattern) {
+            if (str_contains($path, $pattern)) {
+                $matches = true;
+                break;
+            }
+        }
+
+        // Check regex patterns if no string match found
+        if (!$matches) {
+            foreach ($this->regexPatterns as $pattern) {
+                if (preg_match($pattern, $path)) {
+                    $matches = true;
+                    break;
+                }
+            }
+        }
+
+        return $this->negate ? !$matches : $matches;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getChildren(): self
+    {
+        /** @var \RecursiveIterator<string, \SplFileInfo> $inner */
+        $inner = $this->getInnerIterator();
+
+        // Pass all original patterns through (constructor will separate them again)
+        $allPatterns = array_merge($this->stringPatterns, $this->regexPatterns);
+
+        return new self($inner->getChildren(), $allPatterns, $this->negate);
+    }
+}
diff --git a/src/Utility/Fs/Iterator/DepthFilterIterator.php b/src/Utility/Fs/Iterator/DepthFilterIterator.php
new file mode 100644
index 00000000000..4c1f796bb42
--- /dev/null
+++ b/src/Utility/Fs/Iterator/DepthFilterIterator.php
@@ -0,0 +1,87 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use Cake\Utility\Fs\Enum\DepthOperator;
+use FilterIterator;
+use Iterator;
+use RecursiveIteratorIterator;
+
+/**
+ * Filters files by directory depth.
+ *
+ * Uses DepthOperator enum for comparison:
+ * - EQUAL: Depth must equal value
+ * - NOT_EQUAL: Depth must not equal value
+ * - LESS_THAN: Depth must be less than value
+ * - LESS_THAN_OR_EQUAL: Depth must be <= value
+ * - GREATER_THAN: Depth must be greater than value
+ * - GREATER_THAN_OR_EQUAL: Depth must be >= value
+ *
+ * @extends \FilterIterator<string, \SplFileInfo, \Iterator<string, \SplFileInfo>>
+ */
+final class DepthFilterIterator extends FilterIterator
+{
+    /**
+     * @param \Iterator $iterator The iterator to filter (typically RecursiveIteratorIterator)
+     * @param \Cake\Utility\Fs\Enum\DepthOperator $operator Comparison operator
+     * @param int $value Depth value to compare against
+     */
+    public function __construct(
+        Iterator $iterator,
+        protected readonly DepthOperator $operator,
+        protected readonly int $value,
+    ) {
+        parent::__construct($iterator);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        $inner = $this->getInnerIterator();
+
+        // If the inner iterator is a RecursiveIteratorIterator, use its getDepth()
+        if ($inner instanceof RecursiveIteratorIterator) {
+            $depth = $inner->getDepth();
+        } else {
+            // For other iterators wrapped in callbacks/filters, we need to unwrap
+            // until we find the RecursiveIteratorIterator
+            $current = $inner;
+            while ($current instanceof FilterIterator) {
+                $current = $current->getInnerIterator();
+            }
+
+            if ($current instanceof RecursiveIteratorIterator) {
+                $depth = $current->getDepth();
+            } else {
+                // Fallback: can't determine depth, accept everything
+                return true;
+            }
+        }
+
+        return match ($this->operator) {
+            DepthOperator::EQUAL => $depth === $this->value,
+            DepthOperator::NOT_EQUAL => $depth !== $this->value,
+            DepthOperator::LESS_THAN => $depth < $this->value,
+            DepthOperator::LESS_THAN_OR_EQUAL => $depth <= $this->value,
+            DepthOperator::GREATER_THAN => $depth > $this->value,
+            DepthOperator::GREATER_THAN_OR_EQUAL => $depth >= $this->value,
+        };
+    }
+}
diff --git a/src/Utility/Fs/Iterator/ExcludeDirectoryFilterIterator.php b/src/Utility/Fs/Iterator/ExcludeDirectoryFilterIterator.php
new file mode 100644
index 00000000000..d7d7cb4f540
--- /dev/null
+++ b/src/Utility/Fs/Iterator/ExcludeDirectoryFilterIterator.php
@@ -0,0 +1,79 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use RecursiveFilterIterator;
+use RecursiveIterator;
+
+/**
+ * Filters out directories by name during recursive traversal.
+ *
+ * This filter prevents traversal into excluded directories entirely,
+ * making it more efficient than filtering after traversal.
+ *
+ * @internal
+ */
+final class ExcludeDirectoryFilterIterator extends RecursiveFilterIterator
+{
+    /**
+     * Constructor.
+     *
+     * @param \RecursiveIterator<string, \SplFileInfo> $iterator The iterator to filter
+     * @param array<string> $excludeDirs Array of directory names to exclude
+     */
+    public function __construct(
+        RecursiveIterator $iterator,
+        protected readonly array $excludeDirs,
+    ) {
+        parent::__construct($iterator);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        /** @var \SplFileInfo $current */
+        $current = $this->current();
+
+        // Always accept files
+        if (!$current->isDir()) {
+            return true;
+        }
+
+        // Check if directory name matches any excluded names
+        $filename = $current->getFilename();
+        foreach ($this->excludeDirs as $excluded) {
+            if ($filename === $excluded) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getChildren(): self
+    {
+        /** @var \RecursiveIterator<string, \SplFileInfo> $inner */
+        $inner = $this->getInnerIterator();
+
+        return new self($inner->getChildren(), $this->excludeDirs);
+    }
+}
diff --git a/src/Utility/Fs/Iterator/FileTypeFilterIterator.php b/src/Utility/Fs/Iterator/FileTypeFilterIterator.php
new file mode 100644
index 00000000000..1802675173b
--- /dev/null
+++ b/src/Utility/Fs/Iterator/FileTypeFilterIterator.php
@@ -0,0 +1,56 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use Cake\Utility\Fs\Enum\FinderMode;
+use FilterIterator;
+use Iterator;
+
+/**
+ * Filters files by type (files only, directories only, or all).
+ *
+ * @internal
+ * @extends \FilterIterator<string, \SplFileInfo, \Iterator<string, \SplFileInfo>>
+ */
+class FileTypeFilterIterator extends FilterIterator
+{
+    /**
+     * @param \Iterator $iterator The iterator to filter
+     * @param \Cake\Utility\Fs\Enum\FinderMode $mode The mode (FILES, DIRECTORIES, or ALL)
+     */
+    public function __construct(
+        Iterator $iterator,
+        protected readonly FinderMode $mode,
+    ) {
+        parent::__construct($iterator);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        /** @var \SplFileInfo $current */
+        $current = $this->current();
+
+        return match ($this->mode) {
+            FinderMode::FILES => $current->isFile(),
+            FinderMode::DIRECTORIES => $current->isDir(),
+            FinderMode::ALL => true,
+        };
+    }
+}
diff --git a/src/Utility/Fs/Iterator/FilenameFilterIterator.php b/src/Utility/Fs/Iterator/FilenameFilterIterator.php
new file mode 100644
index 00000000000..cd0c0450b09
--- /dev/null
+++ b/src/Utility/Fs/Iterator/FilenameFilterIterator.php
@@ -0,0 +1,69 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use Cake\Utility\Fs\Path;
+use FilterIterator;
+use Iterator;
+
+/**
+ * Filters files by filename using glob patterns.
+ *
+ * Supports glob patterns like:
+ * - `*.php` - All PHP files
+ * - `Test*.php` - Files starting with Test
+ * - `{foo,bar}.php` - foo.php or bar.php
+ *
+ * Can be used to include or exclude files based on the $negate parameter:
+ * - When $negate is false (default): includes files matching patterns
+ * - When $negate is true: excludes files matching patterns
+ *
+ * @extends \FilterIterator<string, \SplFileInfo, \Iterator<string, \SplFileInfo>>
+ */
+final class FilenameFilterIterator extends FilterIterator
+{
+    /**
+     * @param \Iterator<mixed, \SplFileInfo> $iterator The iterator to filter
+     * @param array<string> $patterns Glob patterns to match against
+     * @param bool $negate When true, inverts the filter (excludes matching files)
+     */
+    public function __construct(
+        Iterator $iterator,
+        protected readonly array $patterns,
+        protected readonly bool $negate = false,
+    ) {
+        parent::__construct($iterator);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        $filename = $this->current()->getFilename();
+
+        $matches = false;
+        foreach ($this->patterns as $pattern) {
+            if (Path::matches($pattern, $filename)) {
+                $matches = true;
+                break;
+            }
+        }
+
+        return $this->negate ? !$matches : $matches;
+    }
+}
diff --git a/src/Utility/Fs/Iterator/GlobFilterIterator.php b/src/Utility/Fs/Iterator/GlobFilterIterator.php
new file mode 100644
index 00000000000..61d3c59f2f7
--- /dev/null
+++ b/src/Utility/Fs/Iterator/GlobFilterIterator.php
@@ -0,0 +1,66 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use Cake\Utility\Fs\Path;
+use FilterIterator;
+use Iterator;
+
+/**
+ * Filters files by matching glob patterns against relative paths.
+ *
+ * Supports patterns like:
+ * - `src/**\/*.php` - Recursive matching
+ * - `tests/**\/*Test.php` - Files ending with Test.php
+ * - `*.md` - Files in root directory
+ *
+ * @extends \FilterIterator<string, \SplFileInfo, \Iterator<string, \SplFileInfo>>
+ */
+final class GlobFilterIterator extends FilterIterator
+{
+    /**
+     * @param \Iterator $iterator The iterator to filter
+     * @param array<string> $patterns Glob patterns to match
+     * @param string $basePath Base path to calculate relative paths from
+     */
+    public function __construct(
+        Iterator $iterator,
+        protected readonly array $patterns,
+        protected readonly string $basePath,
+    ) {
+        parent::__construct($iterator);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        $relativePath = Path::makeRelative(
+            $this->current()->getPathname(),
+            $this->basePath,
+        );
+
+        foreach ($this->patterns as $pattern) {
+            if (Path::matches($pattern, $relativePath)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}
diff --git a/src/Utility/Fs/Iterator/HiddenFileFilterIterator.php b/src/Utility/Fs/Iterator/HiddenFileFilterIterator.php
new file mode 100644
index 00000000000..3d605204d39
--- /dev/null
+++ b/src/Utility/Fs/Iterator/HiddenFileFilterIterator.php
@@ -0,0 +1,49 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs\Iterator;
+
+use RecursiveFilterIterator;
+
+/**
+ * Filters out hidden files and directories (those starting with a dot).
+ *
+ * @internal
+ */
+final class HiddenFileFilterIterator extends RecursiveFilterIterator
+{
+    /**
+     * @inheritDoc
+     */
+    public function accept(): bool
+    {
+        /** @var \SplFileInfo $current */
+        $current = $this->current();
+
+        return !str_starts_with($current->getFilename(), '.');
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getChildren(): self
+    {
+        /** @var \RecursiveIterator<string, \SplFileInfo> $inner */
+        $inner = $this->getInnerIterator();
+
+        return new self($inner->getChildren());
+    }
+}
diff --git a/src/Utility/Fs/Path.php b/src/Utility/Fs/Path.php
new file mode 100644
index 00000000000..6e60a2b76cd
--- /dev/null
+++ b/src/Utility/Fs/Path.php
@@ -0,0 +1,148 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Utility\Fs;
+
+/**
+ * Path utility class for cross-platform path manipulation.
+ *
+ * Provides static methods for normalizing, joining, and working with filesystem paths
+ * in a platform-independent way.
+ */
+class Path
+{
+    /**
+     * Normalizes a path by converting directory separators to forward slashes
+     * and removing redundant separators.
+     *
+     * @param string $path The path to normalize
+     * @param bool $trailing Whether to preserve trailing slashes
+     * @return string The normalized path
+     */
+    public static function normalize(string $path, bool $trailing = false): string
+    {
+        // Convert all directory separators to forward slashes
+        $path = str_replace('\\', '/', $path);
+
+        // Remove duplicate slashes
+        $normalized = preg_replace('#/+#', '/', $path);
+        if ($normalized === null) {
+            $normalized = $path;
+        }
+
+        // Handle trailing slash
+        if (!$trailing) {
+            $normalized = rtrim($normalized, '/');
+        } elseif (!str_ends_with($normalized, '/') && $normalized !== '') {
+            $normalized .= '/';
+        }
+
+        return $normalized;
+    }
+
+    /**
+     * Makes a path relative to a base path.
+     *
+     * @param string $path The absolute path to make relative
+     * @param string $from The base path to make relative from
+     * @return string The relative path
+     */
+    public static function makeRelative(string $path, string $from): string
+    {
+        $path = static::normalize($path);
+        $from = static::normalize($from);
+
+        // Split paths into segments
+        $pathParts = explode('/', trim($path, '/'));
+        $fromParts = explode('/', trim($from, '/'));
+
+        // Find common base
+        $commonLength = 0;
+        $maxLength = min(count($pathParts), count($fromParts));
+
+        for ($i = 0; $i < $maxLength; $i++) {
+            if ($pathParts[$i] === $fromParts[$i]) {
+                $commonLength++;
+            } else {
+                break;
+            }
+        }
+
+        // Build relative path
+        $relativeParts = [];
+
+        // Add .. for each directory we need to go up
+        $upCount = count($fromParts) - $commonLength;
+        for ($i = 0; $i < $upCount; $i++) {
+            $relativeParts[] = '..';
+        }
+
+        // Add remaining path segments
+        $relativeParts = array_merge(
+            $relativeParts,
+            array_slice($pathParts, $commonLength),
+        );
+
+        return implode('/', $relativeParts);
+    }
+
+    /**
+     * Joins path segments together using the correct directory separator.
+     *
+     * @param string ...$segments Path segments to join
+     * @return string The joined path
+     */
+    public static function join(string ...$segments): string
+    {
+        if ($segments === []) {
+            return '';
+        }
+
+        $result = str_replace('\\', '/', array_shift($segments));
+
+        foreach ($segments as $segment) {
+            $segment = str_replace('\\', '/', $segment);
+            $result = rtrim($result, '/') . '/' . ltrim($segment, '/');
+        }
+
+        return $result;
+    }
+
+    /**
+     * Checks if a path matches a glob pattern.
+     *
+     * @param string $pattern The glob pattern
+     * @param string $path The path to check
+     * @return bool True if the path matches the pattern
+     */
+    public static function matches(string $pattern, string $path): bool
+    {
+        $pattern = static::normalize($pattern);
+        $path = static::normalize($path);
+
+        // Convert glob pattern to regex
+        $regex = '#^' . preg_quote($pattern, '#') . '$#';
+
+        // Replace glob wildcards
+        $regex = str_replace(
+            ['\*\*', '\*', '\?'],
+            ['.*', '[^/]*', '[^/]'],
+            $regex,
+        );
+
+        return (bool)preg_match($regex, $path);
+    }
+}
diff --git a/src/Utility/Security.php b/src/Utility/Security.php
index b00d3ecc86f..459c9b5e5f4 100644
--- a/src/Utility/Security.php
+++ b/src/Utility/Security.php
@@ -16,6 +16,7 @@
  */
 namespace Cake\Utility;
 
+use Cake\Core\Configure;
 use Cake\Core\Exception\CakeException;
 use Cake\Utility\Crypto\OpenSsl;
 use InvalidArgumentException;
@@ -201,12 +202,13 @@ public static function encrypt(string $plain, string $key, ?string $hmacSalt = n
         self::_checkKey($key, 'encrypt()');
 
         $hmacSalt ??= static::getSalt();
+
         // Generate the encryption and hmac key.
-        $key = mb_substr(hash('sha256', $key . $hmacSalt), 0, 32, '8bit');
+        [$encryptionKey, $hmacKey] = static::makeEncryptionKeys($key, $hmacSalt);
 
         $crypto = static::engine();
-        $ciphertext = $crypto->encrypt($plain, $key);
-        $hmac = hash_hmac('sha256', $ciphertext, $key);
+        $ciphertext = $crypto->encrypt($plain, $encryptionKey);
+        $hmac = hash_hmac('sha256', $ciphertext, $hmacKey);
 
         return $hmac . $ciphertext;
     }
@@ -228,6 +230,35 @@ protected static function _checkKey(string $key, string $method): void
         }
     }
 
+    /**
+     * Generate a key pair of encryption and authentication tokens.
+     *
+     * Encapsulates the two key generation implementations we support.
+     * The previous implementation has a keyspace reduction weakness.
+     *
+     * It is recommended to enable `Security.encryptWithRawKey` in new applications,
+     * to take advantage of longer keys that are longer and have derived encryption
+     * and authentication keys.
+     *
+     * @param string $key The bare key to use.
+     * @param string $hmacSalt The hmac salt to use.
+     * @return array{string, string} A list of $encryption, $authentication keys intended for encrypt() and decrypt().
+     */
+    protected static function makeEncryptionKeys(string $key, string $hmacSalt): array
+    {
+        if (Configure::read('Security.encryptWithRawKey') === true) {
+            $encryption = hash_hkdf('sha256', $key, 32, 'encryption', $hmacSalt);
+            $authentication = hash_hkdf('sha256', $key, 32, 'authentication', $hmacSalt);
+
+            return [$encryption, $authentication];
+        }
+
+        $hashKey = mb_substr(hash('sha256', $key . $hmacSalt), 0, 32, '8bit');
+
+        // The old implementation both keys were the same.
+        return [$hashKey, $hashKey];
+    }
+
     /**
      * Decrypt a value using AES-256.
      *
@@ -247,21 +278,21 @@ public static function decrypt(string $cipher, string $key, ?string $hmacSalt =
         $hmacSalt ??= static::getSalt();
 
         // Generate the encryption and hmac key.
-        $key = mb_substr(hash('sha256', $key . $hmacSalt), 0, 32, '8bit');
+        [$encryptionKey, $hmacKey] = static::makeEncryptionKeys($key, $hmacSalt);
 
         // Split out hmac for comparison
         $macSize = 64;
         $hmac = mb_substr($cipher, 0, $macSize, '8bit');
         $cipher = mb_substr($cipher, $macSize, null, '8bit');
 
-        $compareHmac = hash_hmac('sha256', $cipher, $key);
+        $compareHmac = hash_hmac('sha256', $cipher, $hmacKey);
         if (!static::constantEquals($hmac, $compareHmac)) {
             return null;
         }
 
         $crypto = static::engine();
 
-        return $crypto->decrypt($cipher, $key);
+        return $crypto->decrypt($cipher, $encryptionKey);
     }
 
     /**
diff --git a/src/Utility/Text.php b/src/Utility/Text.php
index 541b2d34d12..8ff8ebbff9d 100644
--- a/src/Utility/Text.php
+++ b/src/Utility/Text.php
@@ -1190,4 +1190,55 @@ public static function slug(string $string, array|string $options = []): string
 
         return (string)preg_replace(array_keys($map), $map, $string);
     }
+
+    /**
+     * Masks a portion of a string with a repeated character.
+     * Replaces characters from $offset to $offset + $length with $maskCharacter.
+     *
+     * If $length is null, it will mask until the end of the string.
+     *
+     * Negative $offset value will count from the end of the string. If the computed $offset is still less than 0, it is clamped to 0.
+     * An $offset at or beyond the string length returns the original string unchanged.
+     *
+     * @param string $string The input string.
+     * @param int $offset Start position of the mask. Negative values count from the end.
+     * @param int|null $length Number of characters to mask. Null masks from $offset to end of string.
+     * @param string $maskCharacter The single Unicode code point character to use as the mask. Defaults to '*'.
+     * @throws \InvalidArgumentException If $maskCharacter is not exactly a single character.
+     * @return string
+     */
+    public static function mask(string $string, int $offset = 0, ?int $length = null, string $maskCharacter = '*'): string
+    {
+        if (mb_strlen($maskCharacter) !== 1) {
+            throw new InvalidArgumentException('Mask character must be a single character.');
+        }
+
+        if ($string === '') {
+            return $string;
+        }
+
+        $stringLength = mb_strlen($string);
+
+        if ($offset < 0) {
+            $offset = max(0, $stringLength + $offset);
+        }
+
+        if ($offset >= $stringLength) {
+            return $string;
+        }
+
+        if ($length !== null && $length <= 0) {
+            return $string;
+        }
+
+        $length = $length === null
+            ? $stringLength - $offset
+            : min($length, $stringLength - $offset);
+
+        $start = mb_substr($string, 0, $offset);
+        $mask = str_repeat($maskCharacter, $length);
+        $end = mb_substr($string, $offset + $length);
+
+        return $start . $mask . $end;
+    }
 }
diff --git a/src/Utility/composer.json b/src/Utility/composer.json
index cb4b0ec9af1..b9d56e6e2f8 100644
--- a/src/Utility/composer.json
+++ b/src/Utility/composer.json
@@ -26,7 +26,7 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0"
+        "cakephp/core": "5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Validation/composer.json b/src/Validation/composer.json
index e888bac34ae..2e91b8f7e50 100644
--- a/src/Validation/composer.json
+++ b/src/Validation/composer.json
@@ -23,12 +23,12 @@
     },
     "require": {
         "php": ">=8.2",
-        "cakephp/core": "^5.3.0",
-        "cakephp/utility": "^5.3.0",
+        "cakephp/core": "5.4.*@dev",
+        "cakephp/utility": "5.4.*@dev",
         "psr/http-message": "^1.1 || ^2.0"
     },
     "require-dev": {
-        "cakephp/i18n": "^5.3.0"
+        "cakephp/i18n": "5.4.*@dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/View/Helper/FormHelper.php b/src/View/Helper/FormHelper.php
index c9bc5c57fa6..6980511d01d 100644
--- a/src/View/Helper/FormHelper.php
+++ b/src/View/Helper/FormHelper.php
@@ -217,7 +217,7 @@ class FormHelper extends Helper
      *
      * @var string|null
      */
-    public ?string $requestType = null;
+    protected ?string $requestType = null;
 
     /**
      * Locator for input widgets.
@@ -816,6 +816,7 @@ public function error(string $field, array|string|null $text = null, array $opti
         return $this->formatTemplate('error', [
             'content' => $error,
             'id' => $this->_domId($field) . '-error',
+            'inputId' => $this->_domId($field),
         ]);
     }
 
@@ -1188,6 +1189,7 @@ public function control(string $fieldName, array $options = []): string
             'errorSuffix' => $errorSuffix,
             'label' => $label,
             'options' => $options,
+            'inputId' => $this->_domId($fieldName),
         ]);
 
         if ($newTemplates) {
@@ -1234,6 +1236,7 @@ protected function _inputContainerTemplate(array $options): string
         return $this->formatTemplate($inputContainerTemplate, [
             'content' => $options['content'],
             'error' => $options['error'],
+            'inputId' => $options['inputId'] ?? '',
             'label' => $options['label'] ?? '',
             'required' => $options['options']['required'] ? ' ' . $this->templater()->get('requiredClass') : '',
             'type' => $options['options']['type'],
@@ -1393,7 +1396,7 @@ protected function _optionsOptions(string $fieldName, array $options): array
      * @param class-string<\BackedEnum> $enumClass Enum class name.
      * @return array<int|string, string>
      */
-    protected function enumOptions(string $enumClass): array
+    public function enumOptions(string $enumClass): array
     {
         assert(is_subclass_of($enumClass, BackedEnum::class));
 
@@ -2442,14 +2445,7 @@ protected function _initInputField(string $field, array $options = []): array
         }
 
         if (!isset($options['name'])) {
-            $endsWithBrackets = '';
-            if (str_ends_with($field, '[]')) {
-                $field = substr($field, 0, -2);
-                $endsWithBrackets = '[]';
-            }
-            $parts = explode('.', $field);
-            $first = array_shift($parts);
-            $options['name'] = $first . ($parts !== [] ? '[' . implode('][', $parts) . ']' : '') . $endsWithBrackets;
+            $options['name'] = $this->_fieldName($field);
         }
 
         if (isset($options['value']) && !isset($options['val'])) {
@@ -2493,6 +2489,29 @@ protected function _initInputField(string $field, array $options = []): array
         return $options;
     }
 
+    /**
+     * Generate the HTML name attribute value from a field name.
+     *
+     * Converts dot notation field names to bracket notation used in HTML forms.
+     * For example, "User.email" becomes "User[email]" and "User.address.city"
+     * becomes "User[address][city]".
+     *
+     * @param string $field Field name in dot notation.
+     * @return string HTML name attribute value.
+     */
+    protected function _fieldName(string $field): string
+    {
+        $endsWithBrackets = '';
+        if (str_ends_with($field, '[]')) {
+            $field = substr($field, 0, -2);
+            $endsWithBrackets = '[]';
+        }
+        $parts = explode('.', $field);
+        $first = array_shift($parts);
+
+        return $first . ($parts !== [] ? '[' . implode('][', $parts) . ']' : '') . $endsWithBrackets;
+    }
+
     /**
      * Determine if a field is disabled.
      *
diff --git a/src/View/Widget/SelectBoxWidget.php b/src/View/Widget/SelectBoxWidget.php
index 4c113f15f2d..383c011b4de 100644
--- a/src/View/Widget/SelectBoxWidget.php
+++ b/src/View/Widget/SelectBoxWidget.php
@@ -16,7 +16,6 @@
  */
 namespace Cake\View\Widget;
 
-use ArrayAccess;
 use Cake\View\Form\ContextInterface;
 use Traversable;
 use function Cake\Core\h;
@@ -198,7 +197,7 @@ protected function _emptyValue(array|string|bool $value): array
      * Render the contents of an optgroup element.
      *
      * @param string $label The optgroup label text
-     * @param \ArrayAccess<string, mixed>|array<string, mixed> $optgroup The optgroup data.
+     * @param iterable $optgroup The optgroup data.
      * @param array<string>|null $disabled The options to disable.
      * @param mixed $selected The options to select.
      * @param array $templateVars Additional template variables.
@@ -207,7 +206,7 @@ protected function _emptyValue(array|string|bool $value): array
      */
     protected function _renderOptgroup(
         string $label,
-        ArrayAccess|array $optgroup,
+        iterable $optgroup,
         ?array $disabled,
         mixed $selected,
         array $templateVars,
@@ -215,10 +214,10 @@ protected function _renderOptgroup(
     ): string {
         $opts = $optgroup;
         $attrs = [];
-        if (isset($optgroup['options'], $optgroup['text'])) {
+        if (is_array($optgroup) && isset($optgroup['options'], $optgroup['text'])) {
             $opts = $optgroup['options'];
             $label = $optgroup['text'];
-            $attrs = (array)$optgroup;
+            $attrs = $optgroup;
         }
         $groupOptions = $this->_renderOptions($opts, $disabled, $selected, $templateVars, $escape);
 
@@ -268,7 +267,7 @@ protected function _renderOptions(
                     )
                 )
             ) {
-                /** @var \ArrayAccess<string, mixed>|array<string, mixed> $val */
+                /** @var iterable $val */
                 $out[] = $this->_renderOptgroup((string)$key, $val, $disabled, $selected, $templateVars, $escape);
                 continue;
             }
diff --git a/tests/TestCase/Collection/CollectionTest.php b/tests/TestCase/Collection/CollectionTest.php
index 9ed8e5ccfd5..d42abcc8d54 100644
--- a/tests/TestCase/Collection/CollectionTest.php
+++ b/tests/TestCase/Collection/CollectionTest.php
@@ -2822,4 +2822,276 @@ public function testExtendedCollectionNoInfiniteLoop(): void
 
         $this->assertSame(3, $count);
     }
+
+    /**
+     * Tests the keys() method returns collection of keys
+     */
+    public function testKeys(): void
+    {
+        $items = ['a' => 1, 'b' => 2, 'c' => 3];
+        $collection = new Collection($items);
+        $keys = $collection->keys()->toList();
+
+        $this->assertSame(['a', 'b', 'c'], $keys);
+    }
+
+    /**
+     * Tests keys() with numeric keys
+     */
+    public function testKeysNumeric(): void
+    {
+        $items = [10 => 'a', 20 => 'b', 30 => 'c'];
+        $collection = new Collection($items);
+        $keys = $collection->keys()->toList();
+
+        $this->assertSame([10, 20, 30], $keys);
+    }
+
+    /**
+     * Tests keys() on empty collection
+     */
+    public function testKeysEmpty(): void
+    {
+        $collection = new Collection([]);
+        $keys = $collection->keys()->toList();
+
+        $this->assertSame([], $keys);
+    }
+
+    /**
+     * Tests the values() method returns re-indexed collection
+     */
+    public function testValues(): void
+    {
+        $items = ['a' => 1, 'b' => 2, 'c' => 3];
+        $collection = new Collection($items);
+        $values = $collection->values()->toArray();
+
+        $this->assertSame([0 => 1, 1 => 2, 2 => 3], $values);
+    }
+
+    /**
+     * Tests values() maintains order
+     */
+    public function testValuesOrder(): void
+    {
+        $items = ['z' => 3, 'a' => 1, 'm' => 2];
+        $collection = new Collection($items);
+        $values = $collection->values()->toList();
+
+        $this->assertSame([3, 1, 2], $values);
+    }
+
+    /**
+     * Tests values() on empty collection
+     */
+    public function testValuesEmpty(): void
+    {
+        $collection = new Collection([]);
+        $values = $collection->values()->toList();
+
+        $this->assertSame([], $values);
+    }
+
+    /**
+     * Tests the implode() method
+     */
+    public function testImplode(): void
+    {
+        $items = ['a', 'b', 'c'];
+        $collection = new Collection($items);
+        $result = $collection->implode(', ');
+
+        $this->assertSame('a, b, c', $result);
+    }
+
+    /**
+     * Tests implode() with path extraction
+     */
+    public function testImplodeWithPath(): void
+    {
+        $items = [
+            ['name' => 'foo'],
+            ['name' => 'bar'],
+            ['name' => 'baz'],
+        ];
+        $collection = new Collection($items);
+        $result = $collection->implode(', ', 'name');
+
+        $this->assertSame('foo, bar, baz', $result);
+    }
+
+    /**
+     * Tests implode() with nested path
+     */
+    public function testImplodeWithNestedPath(): void
+    {
+        $items = [
+            ['user' => ['name' => 'foo']],
+            ['user' => ['name' => 'bar']],
+        ];
+        $collection = new Collection($items);
+        $result = $collection->implode(' - ', 'user.name');
+
+        $this->assertSame('foo - bar', $result);
+    }
+
+    /**
+     * Tests implode() with callable
+     */
+    public function testImplodeWithCallable(): void
+    {
+        $items = [1, 2, 3];
+        $collection = new Collection($items);
+        $result = $collection->implode(', ', fn($v) => $v * 2);
+
+        $this->assertSame('2, 4, 6', $result);
+    }
+
+    /**
+     * Tests implode() with empty collection
+     */
+    public function testImplodeEmpty(): void
+    {
+        $collection = new Collection([]);
+        $result = $collection->implode(', ');
+
+        $this->assertSame('', $result);
+    }
+
+    /**
+     * Tests the when() method applies callback when condition is truthy
+     */
+    public function testWhenTruthy(): void
+    {
+        $items = [1, 2, 3, 4, 5];
+        $collection = new Collection($items);
+
+        $result = $collection->when(true, function ($collection) {
+            return $collection->filter(fn($v) => $v > 2);
+        })->toList();
+
+        $this->assertSame([3, 4, 5], $result);
+    }
+
+    /**
+     * Tests when() does not apply callback when condition is falsy
+     */
+    public function testWhenFalsy(): void
+    {
+        $items = [1, 2, 3, 4, 5];
+        $collection = new Collection($items);
+
+        $result = $collection->when(false, function ($collection) {
+            return $collection->filter(fn($v) => $v > 2);
+        })->toList();
+
+        $this->assertSame([1, 2, 3, 4, 5], $result);
+    }
+
+    /**
+     * Tests when() passes condition value to callback
+     */
+    public function testWhenPassesCondition(): void
+    {
+        $items = [1, 2, 3, 4, 5];
+        $collection = new Collection($items);
+
+        $result = $collection->when(3, function ($collection, $threshold) {
+            return $collection->filter(fn($v) => $v > $threshold);
+        })->toList();
+
+        $this->assertSame([4, 5], $result);
+    }
+
+    /**
+     * Tests when() with zero as falsy condition
+     */
+    public function testWhenZero(): void
+    {
+        $items = [1, 2, 3];
+        $collection = new Collection($items);
+
+        $result = $collection->when(0, function ($collection) {
+            return $collection->filter(fn($v) => $v > 1);
+        })->toList();
+
+        $this->assertSame([1, 2, 3], $result);
+    }
+
+    /**
+     * Tests the unless() method applies callback when condition is falsy
+     */
+    public function testUnlessFalsy(): void
+    {
+        $items = [1, 2, 3, 4, 5];
+        $collection = new Collection($items);
+
+        $result = $collection->unless(false, function ($collection) {
+            return $collection->filter(fn($v) => $v > 2);
+        })->toList();
+
+        $this->assertSame([3, 4, 5], $result);
+    }
+
+    /**
+     * Tests unless() does not apply callback when condition is truthy
+     */
+    public function testUnlessTruthy(): void
+    {
+        $items = [1, 2, 3, 4, 5];
+        $collection = new Collection($items);
+
+        $result = $collection->unless(true, function ($collection) {
+            return $collection->filter(fn($v) => $v > 2);
+        })->toList();
+
+        $this->assertSame([1, 2, 3, 4, 5], $result);
+    }
+
+    /**
+     * Tests unless() with null as falsy condition
+     */
+    public function testUnlessNull(): void
+    {
+        $items = [1, 2, 3];
+        $collection = new Collection($items);
+
+        $result = $collection->unless(null, function ($collection) {
+            return $collection->filter(fn($v) => $v > 1);
+        })->toList();
+
+        $this->assertSame([2, 3], $result);
+    }
+
+    /**
+     * Tests unless() with empty string as falsy condition
+     */
+    public function testUnlessEmptyString(): void
+    {
+        $items = [1, 2, 3];
+        $collection = new Collection($items);
+
+        $result = $collection->unless('', function ($collection) {
+            return $collection->filter(fn($v) => $v > 1);
+        })->toList();
+
+        $this->assertSame([2, 3], $result);
+    }
+
+    /**
+     * Tests chaining when() and unless() together
+     */
+    public function testWhenUnlessChaining(): void
+    {
+        $items = [1, 2, 3, 4, 5];
+        $collection = new Collection($items);
+
+        $result = $collection
+            ->when(true, fn($c) => $c->filter(fn($v) => $v > 1))
+            ->unless(false, fn($c) => $c->filter(fn($v) => $v < 5))
+            ->toList();
+
+        $this->assertSame([2, 3, 4], $result);
+    }
 }
diff --git a/tests/TestCase/Command/CompletionCommandTest.php b/tests/TestCase/Command/CompletionCommandTest.php
index 38a842c50ef..9156bca234d 100644
--- a/tests/TestCase/Command/CompletionCommandTest.php
+++ b/tests/TestCase/Command/CompletionCommandTest.php
@@ -80,7 +80,6 @@ public function testCommands(): void
             'unique',
             'welcome',
             'cache',
-            'help',
             'i18n',
             'plugin',
             'routes',
diff --git a/tests/TestCase/Command/PluginListCommandTest.php b/tests/TestCase/Command/PluginListCommandTest.php
index 1530c0eb20d..ae9f6a66c5b 100644
--- a/tests/TestCase/Command/PluginListCommandTest.php
+++ b/tests/TestCase/Command/PluginListCommandTest.php
@@ -17,7 +17,9 @@
 
 use Cake\Console\CommandInterface;
 use Cake\Console\TestSuite\ConsoleIntegrationTestTrait;
+use Cake\Core\Configure;
 use Cake\Core\Exception\MissingPluginException;
+use Cake\Core\PluginConfig;
 use Cake\TestSuite\TestCase;
 
 /**
@@ -55,6 +57,8 @@ protected function setUp(): void
     protected function tearDown(): void
     {
         parent::tearDown();
+        Configure::delete('plugins');
+        PluginConfig::clearCache();
         if (file_exists($this->pluginsListPath)) {
             $this->deletePhpFile($this->pluginsListPath);
         }
diff --git a/tests/TestCase/Console/BaseCommandTest.php b/tests/TestCase/Console/BaseCommandTest.php
new file mode 100644
index 00000000000..2a8e8c676e5
--- /dev/null
+++ b/tests/TestCase/Console/BaseCommandTest.php
@@ -0,0 +1,212 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Console;
+
+use Cake\Command\Command;
+use Cake\Console\Arguments;
+use Cake\Console\ConsoleIo;
+use Cake\Console\ConsoleOptionParser;
+use Cake\Console\TestSuite\StubConsoleOutput;
+use Cake\TestSuite\TestCase;
+use Mockery;
+
+/**
+ * Test that BaseCommand hydrates $args and $io properties.
+ */
+class BaseCommandTest extends TestCase
+{
+    /**
+     * Test that $this->args is available inside execute()
+     */
+    public function testRunHydratesArgs(): void
+    {
+        $command = new class extends Command {
+            public ?Arguments $capturedArgs = null;
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                $this->capturedArgs = $this->args;
+
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run([], $io);
+
+        $this->assertInstanceOf(Arguments::class, $command->capturedArgs);
+    }
+
+    /**
+     * Test that $this->io is available inside execute()
+     */
+    public function testRunHydratesIo(): void
+    {
+        $command = new class extends Command {
+            public ?ConsoleIo $capturedIo = null;
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                $this->capturedIo = $this->io;
+
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run([], $io);
+
+        $this->assertSame($io, $command->capturedIo);
+    }
+
+    /**
+     * Test that $this->args matches the Arguments passed to execute()
+     */
+    public function testRunHydratedArgsMatchExecuteArgs(): void
+    {
+        $command = new class extends Command {
+            public bool $argsMatch = false;
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                $this->argsMatch = ($this->args === $args);
+
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run([], $io);
+
+        $this->assertTrue($command->argsMatch);
+    }
+
+    /**
+     * Test that $this->args and $this->io are hydrated before execute(),
+     * so traits/parent classes can rely on them without manual assignment.
+     */
+    public function testRunHydratesPropertiesBeforeExecute(): void
+    {
+        $command = new class extends Command {
+            public bool $propsAvailable = false;
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                $this->propsAvailable = isset($this->args) && isset($this->io);
+
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run([], $io);
+
+        $this->assertTrue($command->propsAvailable);
+    }
+
+    /**
+     * Test that $this->io is accessible in initialize()
+     */
+    public function testInitializeCanAccessIo(): void
+    {
+        $command = new class extends Command {
+            public bool $ioAccessible = false;
+
+            public function initialize(): void
+            {
+                $this->ioAccessible = isset($this->io);
+            }
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run([], $io);
+
+        $this->assertTrue($command->ioAccessible);
+    }
+
+    /**
+     * Test that $this->args is accessible in initialize()
+     */
+    public function testInitializeCanAccessArgs(): void
+    {
+        $command = new class extends Command {
+            public bool $argsAccessible = false;
+
+            public function initialize(): void
+            {
+                $this->argsAccessible = isset($this->args);
+            }
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run([], $io);
+
+        $this->assertTrue($command->argsAccessible);
+    }
+
+    /**
+     * Test that hydrated args contain the parsed arguments from the command line.
+     */
+    public function testRunHydratedArgsContainParsedValues(): void
+    {
+        $command = new class extends Command {
+            public ?string $capturedName = null;
+
+            protected function buildOptionParser(ConsoleOptionParser $parser): ConsoleOptionParser
+            {
+                $parser->addArgument('name', ['required' => true]);
+
+                return $parser;
+            }
+
+            public function execute(Arguments $args, ConsoleIo $io): int
+            {
+                $this->capturedName = $this->args->getArgument('name');
+
+                return static::CODE_SUCCESS;
+            }
+        };
+        $command->setName('cake test');
+        $output = new StubConsoleOutput();
+        $io = Mockery::mock(ConsoleIo::class, [$output, $output, null, null])->makePartial();
+
+        $command->run(['Alice'], $io);
+
+        $this->assertSame('Alice', $command->capturedName);
+    }
+}
diff --git a/tests/TestCase/Console/Command/HelpCommandTest.php b/tests/TestCase/Console/Command/HelpCommandTest.php
index a95760a25a9..6247af66120 100644
--- a/tests/TestCase/Console/Command/HelpCommandTest.php
+++ b/tests/TestCase/Console/Command/HelpCommandTest.php
@@ -18,6 +18,7 @@
 
 use Cake\Console\CommandInterface;
 use Cake\Console\TestSuite\ConsoleIntegrationTestTrait;
+use Cake\Core\Configure;
 use Cake\TestSuite\TestCase;
 
 /**
@@ -53,6 +54,7 @@ public function testMainVerbose(): void
     {
         $this->exec('help -v');
         $this->assertExitCode(CommandInterface::CODE_SUCCESS);
+        $this->assertOutputContains('<info>CakePHP:</info>', 'header should appear in verbose mode');
         $this->assertCommandListVerbose();
     }
 
@@ -63,22 +65,41 @@ public function testMainCompact(): void
     {
         $this->exec('help');
         $this->assertExitCode(CommandInterface::CODE_SUCCESS);
+        $this->assertOutputContains('<info>CakePHP:</info>', 'header should appear in compact mode');
         $this->assertOutputContains('<info>Available Commands:</info>', 'single commands header');
         $this->assertOutputContains('<info>routes:</info>', 'routes group header');
         $this->assertOutputContains('<info>cache:</info>', 'cache group header');
-        $this->assertOutputContains('clear', 'cache subcommand listed');
+        $this->assertOutputContains('<comment>cache clear</comment>', 'cache subcommand listed');
         $this->assertOutputContains('Clear all data in a single cache engine', 'inline description shown');
         $this->assertOutputNotContains('<info>app</info>:', 'no plugin group headers in compact mode');
+        $this->assertOutputNotContains('<comment>help</comment>', 'help command should be hidden');
         $this->assertOutputContains('To run a command', 'more info present');
     }
 
+    /**
+     * Test that the default header is omitted when Cake version is unknown.
+     */
+    public function testMainCompactOmitsHeaderWhenVersionUnknown(): void
+    {
+        $version = Configure::read('Cake.version');
+        Configure::write('Cake.version', 'unknown');
+
+        try {
+            $this->exec('help');
+            $this->assertExitCode(CommandInterface::CODE_SUCCESS);
+            $this->assertOutputNotContains('<info>CakePHP:</info>', 'header should be omitted when version is unknown');
+        } finally {
+            Configure::write('Cake.version', $version);
+        }
+    }
+
     /**
      * Assert the verbose help output.
      */
     protected function assertCommandListVerbose(): void
     {
         $this->assertOutputContains('<info>test_plugin</info>', 'plugin header should appear');
-        $this->assertOutputContains('- sample', 'plugin command should appear');
+        $this->assertOutputContains('<comment>sample</comment>', 'plugin command should appear');
         $this->assertOutputNotContains(
             '- test_plugin.sample',
             'only short alias for plugin command.',
@@ -88,18 +109,18 @@ protected function assertCommandListVerbose(): void
             'Abstract command classes should not appear.',
         );
         $this->assertOutputContains('<info>app</info>', 'app header should appear');
-        $this->assertOutputContains('- sample', 'app shell');
+        $this->assertOutputContains('<comment>sample</comment>', 'app shell');
         $this->assertOutputContains('<info>cakephp</info>', 'cakephp header should appear');
-        $this->assertOutputContains('- routes', 'core shell');
-        $this->assertOutputContains('- sample', 'short plugin name');
-        $this->assertOutputContains('- abort', 'command object');
+        $this->assertOutputContains('<comment>routes</comment>', 'core shell');
+        $this->assertOutputContains('<comment>sample</comment>', 'short plugin name');
+        $this->assertOutputContains('<comment>abort</comment>', 'command object');
         $this->assertOutputContains('To run a command', 'more info present');
         $this->assertOutputContains('To get help', 'more info present');
         $this->assertOutputContains('This is a demo command', 'command description missing');
         $this->assertOutputContains('<info>custom_group</info>');
-        $this->assertOutputContains('- grouped');
+        $this->assertOutputContains('<comment>grouped</comment>');
         $this->assertOutputNotContains(
-            '- hidden',
+            '<comment>hidden</comment>',
             'Hidden commands should not appear in help output.',
         );
     }
@@ -112,8 +133,8 @@ public function testFilterByPrefixCompact(): void
         $this->exec('help cache');
         $this->assertExitCode(CommandInterface::CODE_SUCCESS);
         $this->assertOutputContains('<info>cache:</info>');
-        $this->assertOutputContains('cache clear');
-        $this->assertOutputContains('cache list');
+        $this->assertOutputContains('<comment>cache clear</comment>');
+        $this->assertOutputContains('<comment>cache list</comment>');
         $this->assertOutputNotContains('routes');
         $this->assertOutputNotContains('sample');
     }
@@ -126,9 +147,9 @@ public function testFilterByPrefixVerbose(): void
         $this->exec('help cache -v');
         $this->assertExitCode(CommandInterface::CODE_SUCCESS);
         $this->assertOutputContains('Available Commands');
-        $this->assertOutputContains('- cache clear');
+        $this->assertOutputContains('<comment>cache clear</comment>');
         $this->assertOutputContains('Clear all data in a single cache engine');
-        $this->assertOutputNotContains('- routes');
+        $this->assertOutputNotContains('<comment>routes</comment>');
     }
 
     /**
@@ -149,6 +170,7 @@ public function testMainAsXml(): void
 
         $find = '<shell name="test_plugin.sample" call_as="test_plugin.sample" provider="TestPlugin\Command\SampleCommand" help="test_plugin.sample -h"';
         $this->assertOutputContains($find);
+        $this->assertOutputNotContains('<shell name="help"', 'help command should be hidden in XML output');
 
         $this->assertOutputNotContains(
             'HiddenCommand',
diff --git a/tests/TestCase/Console/CommandRunnerTest.php b/tests/TestCase/Console/CommandRunnerTest.php
index ca998316e3b..3fe2a29b645 100644
--- a/tests/TestCase/Console/CommandRunnerTest.php
+++ b/tests/TestCase/Console/CommandRunnerTest.php
@@ -25,6 +25,7 @@
 use Cake\Console\ConsoleIo;
 use Cake\Console\TestSuite\StubConsoleOutput;
 use Cake\Core\Configure;
+use Cake\Core\ConsoleHelpHeaderProviderInterface;
 use Cake\Event\EventManager;
 use Cake\Event\EventManagerInterface;
 use Cake\Http\BaseApplication;
@@ -196,11 +197,38 @@ public function testRunNoCommand(): void
 
         $this->assertSame(0, $result, 'help output is success.');
         $messages = implode("\n", $output->messages());
-        $this->assertStringContainsString('No command provided. Choose one of the available commands', $messages);
+        $this->assertStringNotContainsString('No command provided. Choose one of the available commands', $messages);
         $this->assertStringContainsString('<info>i18n:</info>', $messages);
         $this->assertStringContainsString('Available Commands:', $messages);
     }
 
+    /**
+     * Test that apps can provide a custom help header.
+     */
+    public function testRunNoCommandWithCustomHeaderProvider(): void
+    {
+        $app = new class ($this->config) extends BaseApplication implements ConsoleHelpHeaderProviderInterface
+        {
+            public function middleware(MiddlewareQueue $middlewareQueue): MiddlewareQueue
+            {
+                return $middlewareQueue;
+            }
+
+            public function getConsoleHelpHeader(): string
+            {
+                return '<info>Acme CLI:</info> 1.2.3';
+            }
+        };
+
+        $output = new StubConsoleOutput();
+        $runner = new CommandRunner($app);
+        $result = $runner->run(['cake'], $this->getMockIo($output));
+
+        $this->assertSame(0, $result, 'help output is success.');
+        $messages = implode("\n", $output->messages());
+        $this->assertStringContainsString('<info>Acme CLI:</info> 1.2.3', $messages);
+    }
+
     /**
      * Test using `cake --version` invokes the version command
      */
diff --git a/tests/TestCase/Command/Helper/BannerHelperTest.php b/tests/TestCase/Console/Helper/BannerHelperTest.php
similarity index 96%
rename from tests/TestCase/Command/Helper/BannerHelperTest.php
rename to tests/TestCase/Console/Helper/BannerHelperTest.php
index b2d2b49798c..4a603fb671f 100644
--- a/tests/TestCase/Command/Helper/BannerHelperTest.php
+++ b/tests/TestCase/Console/Helper/BannerHelperTest.php
@@ -14,10 +14,10 @@
  * @since         5.1.0
  * @license       https://opensource.org/licenses/mit-license.php MIT License
  */
-namespace Cake\Test\TestCase\Command\Helper;
+namespace Cake\Test\TestCase\Console\Helper;
 
-use Cake\Command\Helper\BannerHelper;
 use Cake\Console\ConsoleIo;
+use Cake\Console\Helper\BannerHelper;
 use Cake\Console\TestSuite\StubConsoleOutput;
 use Cake\TestSuite\TestCase;
 use InvalidArgumentException;
@@ -28,7 +28,7 @@
 class BannerHelperTest extends TestCase
 {
     /**
-     * @var \Cake\Command\Helper\BannerHelper
+     * @var \Cake\Console\Helper\BannerHelper
      */
     protected BannerHelper $helper;
 
diff --git a/tests/TestCase/Command/Helper/ProgressHelperTest.php b/tests/TestCase/Console/Helper/ProgressHelperTest.php
similarity index 98%
rename from tests/TestCase/Command/Helper/ProgressHelperTest.php
rename to tests/TestCase/Console/Helper/ProgressHelperTest.php
index 2da9d9c0958..29b5d612890 100644
--- a/tests/TestCase/Command/Helper/ProgressHelperTest.php
+++ b/tests/TestCase/Console/Helper/ProgressHelperTest.php
@@ -14,10 +14,10 @@
  * @since         3.1.0
  * @license       https://opensource.org/licenses/mit-license.php MIT License
  */
-namespace Cake\Test\TestCase\Command\Helper;
+namespace Cake\Test\TestCase\Console\Helper;
 
-use Cake\Command\Helper\ProgressHelper;
 use Cake\Console\ConsoleIo;
+use Cake\Console\Helper\ProgressHelper;
 use Cake\Console\TestSuite\StubConsoleOutput;
 use Cake\TestSuite\TestCase;
 use InvalidArgumentException;
@@ -28,7 +28,7 @@
 class ProgressHelperTest extends TestCase
 {
     /**
-     * @var \Cake\Command\Helper\ProgressHelper
+     * @var \Cake\Console\Helper\ProgressHelper
      */
     protected ProgressHelper $helper;
 
diff --git a/tests/TestCase/Command/Helper/TableHelperTest.php b/tests/TestCase/Console/Helper/TableHelperTest.php
similarity index 99%
rename from tests/TestCase/Command/Helper/TableHelperTest.php
rename to tests/TestCase/Console/Helper/TableHelperTest.php
index 77a8067efb5..e1bc2339f2a 100644
--- a/tests/TestCase/Command/Helper/TableHelperTest.php
+++ b/tests/TestCase/Console/Helper/TableHelperTest.php
@@ -14,10 +14,10 @@
  * @since         3.1.0
  * @license       https://opensource.org/licenses/mit-license.php MIT License
  */
-namespace Cake\Test\TestCase\Command\Helper;
+namespace Cake\Test\TestCase\Console\Helper;
 
-use Cake\Command\Helper\TableHelper;
 use Cake\Console\ConsoleIo;
+use Cake\Console\Helper\TableHelper;
 use Cake\Console\TestSuite\StubConsoleOutput;
 use Cake\TestSuite\TestCase;
 use UnexpectedValueException;
diff --git a/tests/TestCase/Command/Helper/TreeHelperTest.php b/tests/TestCase/Console/Helper/TreeHelperTest.php
similarity index 97%
rename from tests/TestCase/Command/Helper/TreeHelperTest.php
rename to tests/TestCase/Console/Helper/TreeHelperTest.php
index d9c7cb13a23..1b05fa32339 100644
--- a/tests/TestCase/Command/Helper/TreeHelperTest.php
+++ b/tests/TestCase/Console/Helper/TreeHelperTest.php
@@ -14,10 +14,10 @@
  * @since         5.3.0
  * @license       https://opensource.org/licenses/mit-license.php MIT License
  */
-namespace Cake\Test\TestCase\Command\Helper;
+namespace Cake\Test\TestCase\Console\Helper;
 
-use Cake\Command\Helper\TreeHelper;
 use Cake\Console\ConsoleIo;
+use Cake\Console\Helper\TreeHelper;
 use Cake\Console\TestSuite\StubConsoleOutput;
 use Cake\TestSuite\TestCase;
 use Stringable;
@@ -31,7 +31,7 @@
 class TreeHelperTest extends TestCase
 {
     /**
-     * @var \Cake\Command\Helper\TreeHelper
+     * @var \Cake\Console\Helper\TreeHelper
      */
     protected TreeHelper $helper;
 
diff --git a/tests/TestCase/Console/HelperRegistryTest.php b/tests/TestCase/Console/HelperRegistryTest.php
index 24bacbc615a..bbd419517f1 100644
--- a/tests/TestCase/Console/HelperRegistryTest.php
+++ b/tests/TestCase/Console/HelperRegistryTest.php
@@ -21,9 +21,9 @@
 use Cake\Console\TestSuite\StubConsoleInput;
 use Cake\Console\TestSuite\StubConsoleOutput;
 use Cake\TestSuite\TestCase;
-use TestApp\Command\Helper\CommandHelper;
-use TestApp\Command\Helper\SimpleHelper;
-use TestPlugin\Command\Helper\ExampleHelper;
+use TestApp\Console\Helper\CommandHelper;
+use TestApp\Console\Helper\SimpleHelper;
+use TestPlugin\Console\Helper\ExampleHelper;
 
 /**
  * HelperRegistryTest
diff --git a/tests/TestCase/Container/Argument/ArgumentResolverTest.php b/tests/TestCase/Container/Argument/ArgumentResolverTest.php
new file mode 100644
index 00000000000..cdfab904b0d
--- /dev/null
+++ b/tests/TestCase/Container/Argument/ArgumentResolverTest.php
@@ -0,0 +1,157 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Argument;
+
+use Cake\Container\Argument\ArgumentResolverInterface;
+use Cake\Container\Argument\ArgumentResolverTrait;
+use Cake\Container\Argument\Literal;
+use Cake\Container\Container;
+use Cake\Container\ContainerAwareTrait;
+use Cake\Test\TestCase\Container\Asset\Baz;
+use Mockery;
+use PHPUnit\Framework\TestCase;
+use Psr\Container\NotFoundExceptionInterface;
+use ReflectionClass;
+use ReflectionFunctionAbstract;
+use ReflectionNamedType;
+use ReflectionParameter;
+
+class ArgumentResolverTest extends TestCase
+{
+    public function testResolverResolvesFromContainer(): void
+    {
+        $resolver = new class implements ArgumentResolverInterface {
+            use ArgumentResolverTrait;
+            use ContainerAwareTrait;
+        };
+
+        $container = Mockery::mock(Container::class);
+
+        $container
+            ->shouldReceive('has')
+            ->with('alias1')
+            ->andReturn(true);
+
+        $container
+            ->shouldReceive('get')
+            ->with('alias1')
+            ->andReturn($resolver);
+
+        $container
+            ->shouldReceive('has')
+            ->with('alias2')
+            ->andReturn(false);
+
+        /** @var Container $container */
+        $resolver->setContainer($container);
+
+        $args = $resolver->resolveArguments(['alias1', 'alias2']);
+
+        $this->assertSame($resolver, $args[0]);
+        $this->assertSame('alias2', $args[1]);
+    }
+
+    public function testResolverResolvesLiteralArguments(): void
+    {
+        $resolver = new class implements ArgumentResolverInterface {
+            use ArgumentResolverTrait;
+            use ContainerAwareTrait;
+        };
+
+        $container = $this->getMockBuilder(Container::class)->getMock();
+
+        $container
+            ->expects($this->once())
+            ->method('has')
+            ->with(self::equalTo('alias1'))
+            ->willReturn(true);
+
+        $container
+            ->expects($this->once())
+            ->method('get')
+            ->with(self::equalTo('alias1'))
+            ->willReturn(new Literal\StringArgument('value1'));
+
+        /** @var Container $container */
+        $resolver->setContainer($container);
+
+        $args = $resolver->resolveArguments(['alias1', new Literal\StringArgument('value2')]);
+
+        self::assertSame('value1', $args[0]);
+        self::assertSame('value2', $args[1]);
+    }
+
+    public function testResolverResolvesArgumentsViaReflection(): void
+    {
+        $method = $this->getMockBuilder(ReflectionFunctionAbstract::class)->getMock();
+        $param1 = $this->getMockBuilder(ReflectionParameter::class)->disableOriginalConstructor()->getMock();
+        $param2 = $this->getMockBuilder(ReflectionParameter::class)->disableOriginalConstructor()->getMock();
+        $param3 = $this->getMockBuilder(ReflectionParameter::class)->disableOriginalConstructor()->getMock();
+        $class = $this->getMockBuilder(ReflectionNamedType::class)->disableOriginalConstructor()->getMock();
+        $container = $this->getMockBuilder(Container::class)->getMock();
+
+        $class->expects(self::once())->method('getName')->willReturn('Class');
+        $param1->expects(self::once())->method('getName')->willReturn('param1');
+        $param1->expects(self::once())->method('getType')->willReturn($class);
+
+        $param2->expects(self::once())->method('getName')->willReturn('param2');
+        $param2->expects(self::once())->method('getType')->willReturn(null);
+        $param2->expects(self::once())->method('isDefaultValueAvailable')->willReturn(true);
+        $param2->expects(self::once())->method('getDefaultValue')->willReturn('value2');
+
+        $param3->expects(self::once())->method('getName')->willReturn('param3');
+
+        $method->expects(self::once())->method('getParameters')->willReturn([$param1, $param2, $param3]);
+
+        $container->expects(self::once())->method('has')->with($this->equalTo('Class'))->willReturn(true);
+        $container->expects(self::once())->method('get')->with($this->equalTo('Class'))->willReturn('classObject');
+
+        $resolver = new class implements ArgumentResolverInterface {
+            use ArgumentResolverTrait;
+            use ContainerAwareTrait;
+        };
+
+        /** @var Container $container */
+        $resolver->setContainer($container);
+
+        $args = $resolver->reflectArguments($method, ['param3' => 'value3']);
+
+        self::assertSame('classObject', $args[0]);
+        self::assertSame('value2', $args[1]);
+        self::assertSame('value3', $args[2]);
+    }
+
+    public function testResolvesDefaultValueArgument(): void
+    {
+        $resolver = new class implements ArgumentResolverInterface {
+            use ArgumentResolverTrait;
+            use ContainerAwareTrait;
+        };
+
+        $result = $resolver->reflectArguments((new ReflectionClass(Baz::class))->getConstructor());
+        self::assertSame([null], $result);
+    }
+
+    public function testResolverThrowsExceptionWhenReflectionDoesNotResolve(): void
+    {
+        $this->expectException(NotFoundExceptionInterface::class);
+
+        $method = $this->getMockBuilder(ReflectionFunctionAbstract::class)->getMock();
+        $param = $this->getMockBuilder(ReflectionParameter::class)->disableOriginalConstructor()->getMock();
+
+        $param->expects(self::once())->method('getName')->willReturn('param1');
+        $param->expects(self::once())->method('getType')->willReturn(null);
+        $param->expects(self::once())->method('isDefaultValueAvailable')->willReturn(false);
+
+        $method->expects(self::once())->method('getParameters')->willReturn([$param]);
+
+        $resolver = new class implements ArgumentResolverInterface {
+            use ArgumentResolverTrait;
+            use ContainerAwareTrait;
+        };
+
+        /** @var ReflectionFunctionAbstract $method */
+        $resolver->reflectArguments($method);
+    }
+}
diff --git a/tests/TestCase/Container/Argument/TypedArgumentTest.php b/tests/TestCase/Container/Argument/TypedArgumentTest.php
new file mode 100644
index 00000000000..69896a1ba2e
--- /dev/null
+++ b/tests/TestCase/Container/Argument/TypedArgumentTest.php
@@ -0,0 +1,38 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Argument;
+
+use Cake\Container\Argument\Literal;
+use Cake\Container\Argument\LiteralArgument;
+use InvalidArgumentException;
+use PHPUnit\Framework\TestCase;
+
+class TypedArgumentTest extends TestCase
+{
+    public function testLiteralArgumentSetsAndGetsArgument(): void
+    {
+        $arguments = [
+            Literal\ArrayArgument::class => [],
+            Literal\BooleanArgument::class => true,
+            Literal\CallableArgument::class => function (): void {
+            },
+            Literal\FloatArgument::class => 1.23,
+            Literal\IntegerArgument::class => 1,
+            Literal\ObjectArgument::class => new class {
+            },
+            Literal\StringArgument::class => 'string',
+        ];
+
+        foreach ($arguments as $type => $expected) {
+            $argument = new $type($expected);
+            self::assertSame($expected, $argument->getValue());
+        }
+    }
+
+    public function testLiteralArgumentThrowsWithWrongArgumentType(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+        new LiteralArgument(LiteralArgument::TYPE_BOOL, 'blah');
+    }
+}
diff --git a/tests/TestCase/Container/Asset/Bar.php b/tests/TestCase/Container/Asset/Bar.php
new file mode 100644
index 00000000000..aaf1eb916d0
--- /dev/null
+++ b/tests/TestCase/Container/Asset/Bar.php
@@ -0,0 +1,14 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+class Bar implements BarInterface
+{
+    protected $something;
+
+    public function setSomething($something): void
+    {
+        $this->something = $something;
+    }
+}
diff --git a/tests/TestCase/Container/Asset/BarInterface.php b/tests/TestCase/Container/Asset/BarInterface.php
new file mode 100644
index 00000000000..26b9b1eba35
--- /dev/null
+++ b/tests/TestCase/Container/Asset/BarInterface.php
@@ -0,0 +1,8 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+interface BarInterface
+{
+}
diff --git a/tests/TestCase/Container/Asset/Baz.php b/tests/TestCase/Container/Asset/Baz.php
new file mode 100644
index 00000000000..ef0a9a5dc97
--- /dev/null
+++ b/tests/TestCase/Container/Asset/Baz.php
@@ -0,0 +1,14 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+class Baz
+{
+    public ?BarInterface $bar;
+
+    public function __construct(?BarInterface $bar = null)
+    {
+        $this->bar = $bar;
+    }
+}
diff --git a/tests/TestCase/Container/Asset/Foo.php b/tests/TestCase/Container/Asset/Foo.php
new file mode 100644
index 00000000000..adca4fd6182
--- /dev/null
+++ b/tests/TestCase/Container/Asset/Foo.php
@@ -0,0 +1,32 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+class Foo
+{
+    public $bar;
+
+    public $myString;
+
+    public static $staticBar;
+
+    public static $staticHello;
+
+    public function __construct(?Bar $bar = null, ?string $myString = null)
+    {
+        $this->bar = $bar;
+        $this->myString = $myString;
+    }
+
+    public function setBar(Bar $bar): void
+    {
+        $this->bar = $bar;
+    }
+
+    public static function staticSetBar(Bar $bar, $hello = 'hello world'): void
+    {
+        self::$staticHello = $hello;
+        self::$staticBar = $bar;
+    }
+}
diff --git a/tests/TestCase/Container/Asset/FooCallable.php b/tests/TestCase/Container/Asset/FooCallable.php
new file mode 100644
index 00000000000..207d564efb2
--- /dev/null
+++ b/tests/TestCase/Container/Asset/FooCallable.php
@@ -0,0 +1,12 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+class FooCallable
+{
+    public function __invoke(Bar $bar): Foo
+    {
+        return new Foo($bar);
+    }
+}
diff --git a/tests/TestCase/Container/Asset/ProBar.php b/tests/TestCase/Container/Asset/ProBar.php
new file mode 100644
index 00000000000..2f4d98c30f0
--- /dev/null
+++ b/tests/TestCase/Container/Asset/ProBar.php
@@ -0,0 +1,16 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+class ProBar implements BarInterface
+{
+    protected function __construct()
+    {
+    }
+
+    public static function factory(): ProBar
+    {
+        return new self();
+    }
+}
diff --git a/tests/TestCase/Container/Asset/ProFoo.php b/tests/TestCase/Container/Asset/ProFoo.php
new file mode 100644
index 00000000000..7acfdd3f77d
--- /dev/null
+++ b/tests/TestCase/Container/Asset/ProFoo.php
@@ -0,0 +1,14 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+class ProFoo
+{
+    public $bar;
+
+    public function __construct(?ProBar $bar = null)
+    {
+        $this->bar = $bar;
+    }
+}
diff --git a/tests/TestCase/Container/Asset/function.php b/tests/TestCase/Container/Asset/function.php
new file mode 100644
index 00000000000..2afe3b875e8
--- /dev/null
+++ b/tests/TestCase/Container/Asset/function.php
@@ -0,0 +1,9 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Asset;
+
+function test(Bar $bar): Foo
+{
+    return new Foo($bar);
+}
diff --git a/tests/TestCase/Container/ContainerTest.php b/tests/TestCase/Container/ContainerTest.php
new file mode 100644
index 00000000000..da578c63459
--- /dev/null
+++ b/tests/TestCase/Container/ContainerTest.php
@@ -0,0 +1,354 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container;
+
+use BadMethodCallException;
+use Cake\Container\Container;
+use Cake\Container\ContainerAwareTrait;
+use Cake\Container\Exception\ContainerException;
+use Cake\Container\Exception\NotFoundException;
+use Cake\Container\ReflectionContainer;
+use Cake\Container\ServiceProvider\AbstractServiceProvider;
+use Cake\Test\TestCase\Container\Asset\Bar;
+use Cake\Test\TestCase\Container\Asset\BarInterface;
+use Cake\Test\TestCase\Container\Asset\Foo;
+use PHPUnit\Framework\TestCase;
+
+class ContainerTest extends TestCase
+{
+    public function testContainerAddsAndGets(): void
+    {
+        $container = new Container();
+        $container->add(Foo::class);
+        self::assertTrue($container->has(Foo::class));
+        $foo = $container->get(Foo::class);
+        self::assertInstanceOf(Foo::class, $foo);
+    }
+
+    public function testContainerAddsAndGetsRecursively(): void
+    {
+        $container = new Container();
+        $container->add(Bar::class, Foo::class);
+        $container->add(Foo::class);
+        self::assertTrue($container->has(Foo::class));
+        $foo = $container->get(Bar::class);
+        self::assertInstanceOf(Foo::class, $foo);
+    }
+
+    public function testContainerAddsMultipleAndGets(): void
+    {
+        $container = new Container();
+        $container->addDefinitions([
+            Foo::class,
+            Bar::class,
+        ]);
+        self::assertTrue($container->has(Foo::class));
+        self::assertTrue($container->has(Bar::class));
+        $foo = $container->get(Foo::class);
+        $bar = $container->get(Bar::class);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $bar);
+    }
+
+    public function testContainerAddsMultipleWithArgsAndGets(): void
+    {
+        $container = new Container();
+        $container->addDefinitions([
+            Foo::class => [Bar::class],
+            Bar::class,
+        ]);
+        self::assertTrue($container->has(Foo::class));
+        self::assertTrue($container->has(Bar::class));
+        $foo = $container->get(Foo::class);
+        $bar = $container->get(Bar::class);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $bar);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+    }
+
+    public function testContainerAddsMultipleWithCustomNamesAndGets(): void
+    {
+        $container = new Container();
+        $container->addDefinitions([
+            'foo' => Foo::class,
+            'bar' => Bar::class,
+        ]);
+        self::assertTrue($container->has('foo'));
+        self::assertTrue($container->has('bar'));
+        $foo = $container->get('foo');
+        $bar = $container->get('bar');
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $bar);
+    }
+
+    public function testContainerAddsAndGetsShared(): void
+    {
+        $container = new Container();
+        $container->addShared(Foo::class);
+        self::assertTrue($container->has(Foo::class));
+
+        $fooOne = $container->get(Foo::class);
+        $fooTwo = $container->get(Foo::class);
+
+        self::assertInstanceOf(Foo::class, $fooOne);
+        self::assertInstanceOf(Foo::class, $fooTwo);
+        self::assertSame($fooOne, $fooTwo);
+    }
+
+    public function testContainerAddsAndGetsSharedByDefault(): void
+    {
+        $container = (new Container())->defaultToShared();
+        $container->add(Foo::class);
+        self::assertTrue($container->has(Foo::class));
+
+        $fooOne = $container->get(Foo::class);
+        $fooTwo = $container->get(Foo::class);
+
+        self::assertInstanceOf(Foo::class, $fooOne);
+        self::assertInstanceOf(Foo::class, $fooTwo);
+        self::assertSame($fooOne, $fooTwo);
+    }
+
+    public function testContainerAddsAndGetsFromTag(): void
+    {
+        $container = new Container();
+        $container->add(Foo::class)->addTag('foobar');
+        $container->add(Bar::class)->addTag('foobar');
+        self::assertTrue($container->has(Foo::class));
+
+        $arrayOf = $container->get('foobar');
+
+        self::assertTrue($container->has('foobar'));
+        self::assertIsArray($arrayOf);
+        self::assertCount(2, $arrayOf);
+        self::assertInstanceOf(Foo::class, $arrayOf[0]);
+        self::assertInstanceOf(Bar::class, $arrayOf[1]);
+    }
+
+    public function testContainerAddsAndGetsNewFromTag(): void
+    {
+        $container = new Container();
+        $container->add(Foo::class)->addTag('foobar');
+        $container->add(Bar::class)->addTag('foobar');
+        self::assertTrue($container->has(Foo::class));
+
+        $arrayOf = $container->get('foobar');
+
+        self::assertTrue($container->has('foobar'));
+        self::assertIsArray($arrayOf);
+        self::assertCount(2, $arrayOf);
+        self::assertInstanceOf(Foo::class, $arrayOf[0]);
+        self::assertInstanceOf(Bar::class, $arrayOf[1]);
+
+        $arrayOfTwo = $container->getNew('foobar');
+        self::assertNotSame($arrayOfTwo, $arrayOf);
+    }
+
+    public function testContainerAddsAndGetsWithServiceProvider(): void
+    {
+        $provider = new class extends AbstractServiceProvider
+        {
+            public function provides(string $id): bool
+            {
+                return $id === Foo::class;
+            }
+
+            public function register(): void
+            {
+                $this->getContainer()->add(Foo::class);
+            }
+        };
+
+        $container = new Container();
+
+        $container->addServiceProvider($provider);
+        self::assertTrue($container->has(Foo::class));
+
+        $foo = $container->get(Foo::class);
+        self::assertInstanceOf(Foo::class, $foo);
+    }
+
+    public function testThrowsWhenServiceProviderLies(): void
+    {
+        $liar = new class extends AbstractServiceProvider
+        {
+            public function provides(string $id): bool
+            {
+                return true;
+            }
+
+            public function register(): void
+            {
+            }
+        };
+
+        $container = new Container();
+
+        $container->addServiceProvider($liar);
+        self::assertTrue($container->has('lie'));
+
+        $this->expectException(ContainerException::class);
+        $container->get('lie');
+    }
+
+    public function testContainerAddsAndGetsFromDelegate(): void
+    {
+        $delegate = new ReflectionContainer();
+        $container = new Container();
+        $container->delegate($delegate);
+        $foo = $container->get(Foo::class);
+        self::assertInstanceOf(Foo::class, $foo);
+    }
+
+    public function testContainerThrowsWhenCannotGetService(): void
+    {
+        $this->expectException(NotFoundException::class);
+        $container = new Container();
+        $container->disableAutoWiring();
+        self::assertFalse($container->has(Foo::class));
+        $container->get(Foo::class);
+    }
+
+    public function testContainerCanExtendDefinition(): void
+    {
+        $container = new Container();
+        $container->add(Foo::class);
+        $definition = $container->extend(Foo::class);
+        self::assertSame(Foo::class, $definition->getAlias());
+        self::assertSame(Foo::class, $definition->getConcrete());
+    }
+
+    public function testContainerCanExtendDefinitionFromServiceProvider(): void
+    {
+        $provider = new class extends AbstractServiceProvider
+        {
+            public function provides(string $id): bool
+            {
+                return $id === Foo::class;
+            }
+
+            public function register(): void
+            {
+                $this->getContainer()->add(Foo::class);
+            }
+        };
+
+        $container = new Container();
+        $container->addServiceProvider($provider);
+        $definition = $container->extend(Foo::class);
+        self::assertSame(Foo::class, $definition->getAlias());
+        self::assertSame(Foo::class, $definition->getConcrete());
+    }
+
+    public function testContainerThrowsWhenCannotGetDefinitionToExtend(): void
+    {
+        $this->expectException(NotFoundException::class);
+        $container = new Container();
+        $container->disableAutoWiring();
+        self::assertFalse($container->has(Foo::class));
+        $container->extend(Foo::class);
+    }
+
+    public function testContainerAddsAndInvokesInflector(): void
+    {
+        $container = new Container();
+        $container->inflector(Foo::class)->setProperty('bar', Bar::class);
+        $container->add(Foo::class);
+        $container->add(Bar::class);
+        $foo = $container->get(Foo::class);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+    }
+
+    public function testContainerAwareCannotBeUsedWithoutImplementingInterface(): void
+    {
+        $this->expectException(BadMethodCallException::class);
+
+        $class = new class {
+            use ContainerAwareTrait;
+        };
+
+        $container = new Container();
+        $class->setContainer($container);
+    }
+
+    public function testNonExistentClassCausesException(): void
+    {
+        $container = new Container();
+        $nonExistent = 'Cake\Test\TestCase\Container\NonExistent';
+        $container->add($nonExistent);
+
+        self::assertTrue($container->has($nonExistent));
+        self::assertSame($nonExistent, $container->get($nonExistent));
+    }
+
+    /**
+     * Test that named arguments work when all required arguments are provided.
+     *
+     * Note: Partial autowiring (where some args are named and others are auto-wired)
+     * is not yet supported in Definition. For that use case, use Container::make().
+     */
+    public function testContainerResolvesWithNamedArgument(): void
+    {
+        $container = new Container();
+        $container->add(Foo::class)
+            ->addArgument(Bar::class, 'bar')
+            ->addArgument('something', 'myString');
+        self::assertTrue($container->has(Foo::class));
+        $foo = $container->get(Foo::class);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+        self::assertSame('something', $foo->myString);
+    }
+
+    public function testContainerMakeWithArgs(): void
+    {
+        $container = new Container();
+        $foo = $container->make(Foo::class, ['myString' => 'hello world']);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+        self::assertSame('hello world', $foo->myString);
+    }
+
+    public function testContainerMakeAlwaysReturnsNewInstance(): void
+    {
+        $container = new Container();
+        $fooOne = $container->make(Foo::class);
+        $fooTwo = $container->make(Foo::class);
+        self::assertNotSame($fooOne, $fooTwo);
+    }
+
+    public function testInterfaceToImplementationUsesExistingDefinition(): void
+    {
+        $container = new Container();
+        // Register Bar with specific configuration
+        $container->addShared(Bar::class);
+
+        // Map interface to the concrete class
+        $container->add(BarInterface::class, Bar::class);
+
+        // Get via interface should use the existing Bar definition
+        $barFromInterface = $container->get(BarInterface::class);
+        $barDirect = $container->get(Bar::class);
+
+        self::assertInstanceOf(Bar::class, $barFromInterface);
+        // Should be the same instance because Bar is shared
+        self::assertSame($barDirect, $barFromInterface);
+    }
+
+    public function testHasDefinitionOnlyChecksExplicitDefinitions(): void
+    {
+        $container = new Container();
+        $container->add(Foo::class);
+
+        // hasDefinition should return true for explicitly added definitions
+        self::assertTrue($container->hasDefinition(Foo::class));
+
+        // hasDefinition should return false for autowirable classes not explicitly added
+        self::assertFalse($container->hasDefinition(Bar::class));
+
+        // but has() should return true because autowiring can resolve it
+        self::assertTrue($container->has(Bar::class));
+    }
+}
diff --git a/tests/TestCase/Container/Definition/DefinitionAggregateTest.php b/tests/TestCase/Container/Definition/DefinitionAggregateTest.php
new file mode 100644
index 00000000000..09c14193d86
--- /dev/null
+++ b/tests/TestCase/Container/Definition/DefinitionAggregateTest.php
@@ -0,0 +1,270 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Definition;
+
+use Cake\Container\Container;
+use Cake\Container\Definition\Definition;
+use Cake\Container\Definition\DefinitionAggregate;
+use Cake\Container\Definition\DefinitionInterface;
+use Cake\Container\Exception\NotFoundException;
+use Cake\Test\TestCase\Container\Asset\Foo;
+use Mockery;
+use PHPUnit\Framework\TestCase;
+
+class DefinitionAggregateTest extends TestCase
+{
+    public function testAggregateAddsDefinition(): void
+    {
+        $container = new Container();
+        $definition = Mockery::mock(DefinitionInterface::class);
+
+        $definition
+            ->shouldReceive('setAlias')
+            ->once()
+            ->with('alias')
+            ->andReturnSelf();
+
+        $aggregate = (new DefinitionAggregate())->setContainer($container);
+        $definition = $aggregate->add('alias', $definition);
+
+        self::assertInstanceOf(DefinitionInterface::class, $definition);
+    }
+
+    public function testAggregateCreatesDefinition(): void
+    {
+        $container = new Container();
+        $aggregate = (new DefinitionAggregate())->setContainer($container);
+        $definition = $aggregate->add('alias', Foo::class);
+        self::assertSame('alias', $definition->getAlias());
+    }
+
+    public function testAggregateHasDefinition(): void
+    {
+        $container = new Container();
+        $aggregate = (new DefinitionAggregate())->setContainer($container);
+        $aggregate->add('alias', Foo::class);
+        self::assertTrue($aggregate->has('alias'));
+        self::assertFalse($aggregate->has('nope'));
+    }
+
+    public function testAggregateAddsAndIteratesMultipleDefinitions(): void
+    {
+        $container = new Container();
+        $aggregate = (new DefinitionAggregate())->setContainer($container);
+
+        $definitions = [];
+
+        for ($i = 0; $i < 10; $i++) {
+            $definitions[] = $aggregate->add('alias' . $i, Foo::class);
+        }
+
+        foreach ($aggregate->getIterator() as $key => $definition) {
+            self::assertSame($definitions[$key], $definition);
+        }
+    }
+
+    public function testAggregateIteratesAndResolvesDefinition(): void
+    {
+        $aggregate = new DefinitionAggregate();
+        $definition1 = Mockery::mock(DefinitionInterface::class);
+        $definition2 = Mockery::mock(DefinitionInterface::class);
+        $container = new Container();
+
+        $definition1
+            ->shouldReceive('getAlias')
+            ->once()
+            ->andReturn('alias1');
+
+        $definition1
+            ->shouldReceive('setAlias')
+            ->once()
+            ->with('alias1')
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('getAlias')
+            ->once()
+            ->andReturn('alias2');
+
+        $definition2
+            ->shouldReceive('setContainer')
+            ->once()
+            ->with($container)
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('setShared')
+            ->once()
+            ->with(true)
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('setAlias')
+            ->once()
+            ->with('alias2')
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('resolve')
+            ->once()
+            ->andReturnSelf();
+
+        $aggregate->setContainer($container);
+
+        $aggregate->add('alias1', $definition1);
+        $aggregate->addShared('alias2', $definition2);
+
+        $resolved = $aggregate->resolve('alias2');
+        self::assertSame($definition2, $resolved);
+    }
+
+    public function testAggregateCanResolveArrayOfTaggedDefinitions(): void
+    {
+        $definition1 = Mockery::mock(DefinitionInterface::class);
+        $definition2 = Mockery::mock(DefinitionInterface::class);
+        $container = new Container();
+
+        $definition1
+            ->shouldReceive('setContainer')
+            ->once()
+            ->with($container)
+            ->andReturnSelf();
+
+        $definition1
+            ->shouldReceive('hasTag')
+            ->twice()
+            ->with('tag')
+            ->andReturn(true);
+
+        $definition1
+            ->shouldReceive('resolve')
+            ->once()
+            ->andReturn('definition1');
+
+        $definition2
+            ->shouldReceive('setContainer')
+            ->once()
+            ->with($container)
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('hasTag')
+            ->once()
+            ->with('tag')
+            ->andReturn(true);
+
+        $definition2
+            ->shouldReceive('resolve')
+            ->once()
+            ->andReturn('definition2');
+
+        $aggregate = new DefinitionAggregate([$definition1, $definition2]);
+
+        $aggregate->setContainer($container);
+        self::assertTrue($aggregate->hasTag('tag'));
+        $resolved = $aggregate->resolveTagged('tag');
+        self::assertSame(['definition1', 'definition2'], $resolved);
+    }
+
+    public function testAggregateThrowsExceptionWhenCannotResolve(): void
+    {
+        $this->expectException(NotFoundException::class);
+
+        $aggregate = new DefinitionAggregate();
+        $definition1 = Mockery::mock(DefinitionInterface::class);
+        $definition2 = Mockery::mock(DefinitionInterface::class);
+        $container = new Container();
+
+        $definition1
+            ->shouldReceive('getAlias')
+            ->once()
+            ->andReturn('alias1');
+
+        $definition1
+            ->shouldReceive('setAlias')
+            ->once()
+            ->with('alias1')
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('getAlias')
+            ->once()
+            ->andReturn('alias2');
+
+        $definition2
+            ->shouldReceive('setShared')
+            ->once()
+            ->with(true)
+            ->andReturnSelf();
+
+        $definition2
+            ->shouldReceive('setAlias')
+            ->once()
+            ->with('alias2')
+            ->andReturnSelf();
+
+        $aggregate->setContainer($container);
+
+        $aggregate->add('alias1', $definition1);
+        $aggregate->addShared('alias2', $definition2);
+
+        $aggregate->resolveNew('alias');
+    }
+
+    public function testDefinitionPrecedingSlash(): void
+    {
+        $container = new Container();
+        $aggregate = new DefinitionAggregate();
+        $aggregate->setContainer($container);
+
+        $some_class = '\\Cake\\Test\\TestCase\\Container\\Asset\\Foo';
+        $aggregate->add($some_class, null);
+
+        $definition = $aggregate->getDefinition(Foo::class);
+
+        self::assertInstanceOf(Definition::class, $definition);
+    }
+
+    public function testGetPrecedingSlash(): void
+    {
+        $container = new Container();
+        $aggregate = new DefinitionAggregate();
+        $aggregate->setContainer($container);
+
+        $some_class = Foo::class;
+        $aggregate->add($some_class, null);
+
+        $definition = $aggregate->getDefinition('\\Cake\\Test\\TestCase\\Container\\Asset\\Foo');
+
+        self::assertInstanceOf(Definition::class, $definition);
+    }
+
+    public function testDefinitionPrecedingSlashSingularQuotes(): void
+    {
+        $container = new Container();
+        $aggregate = new DefinitionAggregate();
+        $aggregate->setContainer($container);
+
+        $some_class = '\\Cake\\Test\\TestCase\\Container\\Asset\\Foo';
+        $aggregate->add($some_class, null);
+
+        $definition = $aggregate->getDefinition(Foo::class);
+
+        self::assertInstanceOf(Definition::class, $definition);
+    }
+
+    public function testGetPrecedingSlashSingularQuote(): void
+    {
+        $container = new Container();
+        $aggregate = new DefinitionAggregate();
+        $aggregate->setContainer($container);
+
+        $some_class = Foo::class;
+        $aggregate->add($some_class, null);
+
+        $definition = $aggregate->getDefinition('\\Cake\\Test\\TestCase\\Container\\Asset\\Foo');
+
+        self::assertInstanceOf(Definition::class, $definition);
+    }
+}
diff --git a/tests/TestCase/Container/Definition/DefinitionTest.php b/tests/TestCase/Container/Definition/DefinitionTest.php
new file mode 100644
index 00000000000..6aceb62c829
--- /dev/null
+++ b/tests/TestCase/Container/Definition/DefinitionTest.php
@@ -0,0 +1,159 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Definition;
+
+use Cake\Container\Argument\Literal;
+use Cake\Container\Argument\ResolvableArgument;
+use Cake\Container\Container;
+use Cake\Container\Definition\Definition;
+use Cake\Test\TestCase\Container\Asset\Bar;
+use Cake\Test\TestCase\Container\Asset\Foo;
+use Cake\Test\TestCase\Container\Asset\FooCallable;
+use Error;
+use PHPUnit\Framework\TestCase;
+
+class DefinitionTest extends TestCase
+{
+    public function testDefinitionResolvesClosureWithDefinedArgs(): void
+    {
+        $definition = new Definition('callable', function (...$args) {
+            return implode(' ', $args);
+        });
+
+        $definition->addArguments(['hello', 'world']);
+        $actual = $definition->resolve();
+        self::assertSame('hello world', $actual);
+    }
+
+    public function testDefinitionResolvesClosureReturningRawArgument(): void
+    {
+        $definition = new Definition('callable', function () {
+            return new Literal\StringArgument('hello world');
+        });
+
+        $actual = $definition->resolve();
+        self::assertSame('hello world', $actual);
+    }
+
+    public function testDefinitionResolvesCallableClass(): void
+    {
+        $definition = new Definition('callable', new FooCallable());
+        $definition->addArgument(new Bar());
+        $actual = $definition->resolve();
+        self::assertInstanceOf(Foo::class, $actual);
+    }
+
+    public function testDefinitionResolvesArrayCallable(): void
+    {
+        $definition = new Definition('callable', [new FooCallable(), '__invoke']);
+        $definition->addArgument(new Bar());
+        $actual = $definition->resolve();
+        self::assertInstanceOf(Foo::class, $actual);
+    }
+
+    public function testDefinitionAddsArgumentWithName(): void
+    {
+        $definition = new Definition('class', Foo::class);
+        $definition->addArgument('something', 'myString');
+        $actual = $definition->resolve();
+        self::assertInstanceOf(Foo::class, $actual);
+        self::assertSame('something', $actual->myString);
+    }
+
+    public function testDefinitionAddsArgumentWithUnknownNameThrows(): void
+    {
+        $definition = new Definition('class', Foo::class);
+        $definition->addArgument('something', 'unknown');
+        $this->expectException(Error::class);
+        $this->expectExceptionMessage('Unknown named parameter $unknown');
+        $definition->resolve();
+    }
+
+    public function testDefinitionResolvesClassWithMethodCalls(): void
+    {
+        $container = $this->getMockBuilder(Container::class)->getMock();
+        $bar = new Bar();
+
+        $container->expects(self::once())->method('has')->with(self::equalTo(Bar::class))->willReturn(true);
+        $container->expects(self::once())->method('get')->with(self::equalTo(Bar::class))->willReturn($bar);
+
+        $definition = new Definition('callable', Foo::class);
+
+        $definition->setContainer($container);
+        $definition->addMethodCalls(['setBar' => [Bar::class]]);
+
+        $actual = $definition->resolve();
+        self::assertInstanceOf(Foo::class, $actual);
+        self::assertInstanceOf(Bar::class, $actual->bar);
+    }
+
+    public function testDefinitionResolvesClassWithDefinedArgs(): void
+    {
+        $container = $this->getMockBuilder(Container::class)->getMock();
+        $bar = new Bar();
+
+        $container->expects(self::once())->method('has')->with(self::equalTo(Bar::class))->willReturn(true);
+        $container->expects(self::once())->method('get')->with(self::equalTo(Bar::class))->willReturn($bar);
+
+        $definition = new Definition('callable', Foo::class);
+
+        $definition->setContainer($container);
+        $definition->addArgument(Bar::class);
+
+        $actual = $definition->resolve();
+        self::assertInstanceOf(Foo::class, $actual);
+        self::assertInstanceOf(Bar::class, $actual->bar);
+    }
+
+    public function testDefinitionResolvesSharedItemOnlyOnce(): void
+    {
+        $definition = new Definition('class', Foo::class);
+        $definition->setShared(true);
+        $actual1 = $definition->resolve();
+        $actual2 = $definition->resolve();
+        $actual3 = $definition->resolveNew();
+        self::assertSame($actual1, $actual2);
+        self::assertNotSame($actual1, $actual3);
+    }
+
+    public function testDefinitionResolvesNestedAlias(): void
+    {
+        $aliasDefinition = new Definition('alias', new ResolvableArgument('class'));
+        $definition = new Definition('class', Foo::class);
+        $container = $this->getMockBuilder(Container::class)->getMock();
+
+        $expected = $definition->resolve();
+
+        $container->expects(self::once())->method('has')->with(self::equalTo('class'))->willReturn(true);
+        $container->expects(self::once())->method('get')->with(self::equalTo('class'))->willReturn($expected);
+
+        $aliasDefinition->setContainer($container);
+        $actual = $aliasDefinition->resolve();
+        self::assertSame($expected, $actual);
+    }
+
+    public function testDefinitionCanAddTags(): void
+    {
+        $definition = new Definition('class', Foo::class);
+        $definition->addTag('tag1')->addTag('tag2');
+        self::assertTrue($definition->hasTag('tag1'));
+        self::assertTrue($definition->hasTag('tag2'));
+        self::assertFalse($definition->hasTag('tag3'));
+    }
+
+    public function testDefinitionCanGetConcrete(): void
+    {
+        $concrete = new Literal\StringArgument(Foo::class);
+        $definition = new Definition('class', $concrete);
+        self::assertSame($concrete, $definition->getConcrete());
+    }
+
+    public function testDefinitionCanSetConcrete(): void
+    {
+        $definition = new Definition('class');
+        $concrete = new Literal\StringArgument(Foo::class);
+        $definition->setConcrete($concrete);
+        self::assertSame($concrete, $definition->getConcrete());
+    }
+}
diff --git a/tests/TestCase/Container/Inflector/InflectorAggregateTest.php b/tests/TestCase/Container/Inflector/InflectorAggregateTest.php
new file mode 100644
index 00000000000..438536b0282
--- /dev/null
+++ b/tests/TestCase/Container/Inflector/InflectorAggregateTest.php
@@ -0,0 +1,87 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Inflector;
+
+use Cake\Container\Container;
+use Cake\Container\ContainerAwareInterface;
+use Cake\Container\DefinitionContainerInterface;
+use Cake\Container\Inflector\InflectorAggregate;
+use DateTimeZone;
+use PHPUnit\Framework\TestCase;
+
+class InflectorAggregateTest extends TestCase
+{
+    public function testAggregateAddsInflector(): void
+    {
+        $aggregate = new InflectorAggregate();
+        $inflector = $aggregate->add('Some\Type');
+        self::assertSame('Some\Type', $inflector->getType());
+    }
+
+    public function testAggregateAddsAndIteratesMultipleInflectors(): void
+    {
+        $aggregate = new InflectorAggregate();
+        $inflectors = [];
+
+        for ($i = 0; $i < 10; $i++) {
+            $inflectors[] = $aggregate->add('Some\Type' . $i);
+        }
+
+        foreach ($aggregate->getIterator() as $key => $inflector) {
+            self::assertSame($inflectors[$key], $inflector);
+        }
+    }
+
+    public function testAggregateIteratesAndInflectsOnObject(): void
+    {
+        $aggregate = new InflectorAggregate();
+        $containerAware = new class implements ContainerAwareInterface {
+            public ?DefinitionContainerInterface $container = null;
+
+            public function getContainer(): DefinitionContainerInterface
+            {
+                return $this->container;
+            }
+
+            public function setContainer(DefinitionContainerInterface $container): ContainerAwareInterface
+            {
+                $this->container = $container;
+
+                return $this;
+            }
+        };
+        $container = new Container();
+        $aggregate->add(ContainerAwareInterface::class)->invokeMethod('setContainer', [$container]);
+        $aggregate->add('Ignored\Type');
+        $aggregate->setContainer($container);
+        $aggregate->inflect($containerAware);
+        self::assertSame($container, $containerAware->container);
+    }
+
+    public function testNoInflectionIsAttemptedOnNonObjects(): void
+    {
+        $container = new Container();
+
+        $types = [
+            'my-array' => [1, 2, 3],
+            'my-number' => 123,
+            'my-string' => 'foo bar',
+            'my-generated-array' => [DateTimeZone::class, 'listIdentifiers'],
+            'my-generated-number' => 'time',
+            'my-generated-string' => function (): string {
+                return 'blahblahblah';
+            },
+        ];
+
+        foreach ($types as $alias => $concrete) {
+            $container->add($alias, $concrete);
+
+            if (is_callable($concrete)) {
+                $concrete = $concrete();
+            }
+
+            self::assertSame($container->get($alias), $concrete);
+        }
+    }
+}
diff --git a/tests/TestCase/Container/Inflector/InflectorTest.php b/tests/TestCase/Container/Inflector/InflectorTest.php
new file mode 100644
index 00000000000..1b70573fd29
--- /dev/null
+++ b/tests/TestCase/Container/Inflector/InflectorTest.php
@@ -0,0 +1,123 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\Inflector;
+
+use Cake\Container\Container;
+use Cake\Container\Inflector\Inflector;
+use Cake\Test\TestCase\Container\Asset\Bar;
+use PHPUnit\Framework\TestCase;
+use ReflectionClass;
+
+class InflectorTest extends TestCase
+{
+    public function testInflectorSetsExpectedMethodCalls(): void
+    {
+        $container = new Container();
+        $inflector = (new Inflector('Type'))->setContainer($container);
+
+        $inflector->invokeMethod('method1', ['arg1']);
+
+        $inflector->invokeMethods([
+            'method2' => ['arg1'],
+            'method3' => ['arg1'],
+        ]);
+
+        $methods = (new ReflectionClass($inflector))->getProperty('methods');
+
+        self::assertSame($methods->getValue($inflector), [
+            'method1' => ['arg1'],
+            'method2' => ['arg1'],
+            'method3' => ['arg1'],
+        ]);
+    }
+
+    public function testInflectorSetsExpectedProperties(): void
+    {
+        $container = new Container();
+        $inflector = (new Inflector('Type'))->setContainer($container);
+
+        $inflector->setProperty('property1', 'value');
+
+        $inflector->setProperties([
+            'property2' => 'value',
+            'property3' => 'value',
+        ]);
+
+        $properties = (new ReflectionClass($inflector))->getProperty('properties');
+
+        self::assertSame($properties->getValue($inflector), [
+            'property1' => 'value',
+            'property2' => 'value',
+            'property3' => 'value',
+        ]);
+    }
+
+    public function testInflectorInflectsWithProperties(): void
+    {
+        $container = new Container();
+
+        $bar = new class {
+        };
+
+        $container->add(Bar::class, $bar);
+
+        $inflector = (new Inflector('Type'))
+            ->setContainer($container)
+            ->setProperty('bar', Bar::class);
+
+        $foo = new class {
+            public $bar;
+        };
+
+        $inflector->inflect($foo);
+
+        self::assertSame($bar, $foo->bar);
+    }
+
+    public function testInflectorInflectsWithMethodCall(): void
+    {
+        $container = new Container();
+
+        $bar = new class {
+        };
+
+        $container->add(Bar::class, $bar);
+
+        $inflector = (new Inflector('Type'))
+            ->setContainer($container)
+            ->invokeMethod('setBar', [Bar::class]);
+
+        $foo = new class {
+            public $bar;
+            public function setBar($bar): void
+            {
+                $this->bar = $bar;
+            }
+        };
+
+        $inflector->inflect($foo);
+        self::assertSame($bar, $foo->bar);
+    }
+
+    public function testInflectorInflectsWithCallback(): void
+    {
+        $foo = new class {
+            public $bar;
+            public function setBar($bar): void
+            {
+                $this->bar = $bar;
+            }
+        };
+
+        $bar = new class {
+        };
+
+        $inflector = new Inflector('Type', function ($object) use ($bar): void {
+            $object->setBar($bar);
+        });
+
+        $inflector->inflect($foo);
+        self::assertSame($bar, $foo->bar);
+    }
+}
diff --git a/tests/TestCase/Container/ReflectionContainerTest.php b/tests/TestCase/Container/ReflectionContainerTest.php
new file mode 100644
index 00000000000..c9f7a00a2e5
--- /dev/null
+++ b/tests/TestCase/Container/ReflectionContainerTest.php
@@ -0,0 +1,223 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container;
+
+use Cake\Container\Container;
+use Cake\Container\Exception\NotFoundException;
+use Cake\Container\ReflectionContainer;
+use Cake\Test\TestCase\Container\Asset\Bar;
+use Cake\Test\TestCase\Container\Asset\Foo;
+use Cake\Test\TestCase\Container\Asset\FooCallable;
+use Cake\Test\TestCase\Container\Asset\ProBar;
+use Cake\Test\TestCase\Container\Asset\ProFoo;
+use PHPUnit\Framework\TestCase;
+use stdClass;
+
+class ReflectionContainerTest extends TestCase
+{
+    private function getContainer(array $items = []): Container
+    {
+        $container = new Container();
+        $container->disableAutoWiring();
+        foreach ($items as $alias => $item) {
+            $container->addShared($alias, $item);
+        }
+
+        return $container;
+    }
+
+    public function testHasReturnsTrueIfClassExists(): void
+    {
+        $container = new ReflectionContainer();
+        self::assertTrue($container->has(ReflectionContainer::class));
+    }
+
+    public function testHasReturnsFalseIfClassDoesNotExist(): void
+    {
+        $container = new ReflectionContainer();
+        self::assertFalse($container->has('blah'));
+    }
+
+    public function testContainerInstantiatesClassWithoutConstructor(): void
+    {
+        $classWithoutConstructor = stdClass::class;
+        $container = new ReflectionContainer();
+        self::assertInstanceOf($classWithoutConstructor, $container->get($classWithoutConstructor));
+    }
+
+    public function testContainerInstantiatesAndCachesClassWithoutConstructor(): void
+    {
+        $classWithoutConstructor = stdClass::class;
+        $container = new ReflectionContainer(true);
+
+        $classWithoutConstructorOne = $container->get($classWithoutConstructor);
+        $classWithoutConstructorTwo = $container->get($classWithoutConstructor);
+
+        self::assertInstanceOf($classWithoutConstructor, $classWithoutConstructorOne);
+        self::assertInstanceOf($classWithoutConstructor, $classWithoutConstructorTwo);
+        self::assertSame($classWithoutConstructorOne, $classWithoutConstructorTwo);
+    }
+
+    public function testGetInstantiatesClassWithConstructor(): void
+    {
+        $classWithConstructor = Foo::class;
+        $dependencyClass = Bar::class;
+
+        $container = new ReflectionContainer();
+        $item = $container->get($classWithConstructor);
+
+        self::assertInstanceOf($classWithConstructor, $item);
+        self::assertInstanceOf($dependencyClass, $item->bar);
+    }
+
+    public function testGetInstantiatesAndCachedClassWithConstructor(): void
+    {
+        $classWithConstructor = Foo::class;
+        $dependencyClass = Bar::class;
+
+        $container = new ReflectionContainer(true);
+
+        $itemOne = $container->get($classWithConstructor);
+        $itemTwo = $container->get($classWithConstructor);
+
+        self::assertInstanceOf($classWithConstructor, $itemOne);
+        self::assertInstanceOf($dependencyClass, $itemOne->bar);
+
+        self::assertInstanceOf($classWithConstructor, $itemTwo);
+        self::assertInstanceOf($dependencyClass, $itemTwo->bar);
+
+        self::assertSame($itemOne, $itemTwo);
+        self::assertSame($itemOne->bar, $itemTwo->bar);
+    }
+
+    public function testGetInstantiatesClassWithConstructorAndUsesContainer(): void
+    {
+        $classWithConstructor = Foo::class;
+        $dependencyClass = Bar::class;
+
+        $dependency = new $dependencyClass();
+        $container = new ReflectionContainer();
+
+        $container->setContainer($this->getContainer([
+            $dependencyClass => $dependency,
+        ]));
+
+        $item = $container->get($classWithConstructor);
+
+        self::assertInstanceOf($classWithConstructor, $item);
+        self::assertSame($dependency, $item->bar);
+    }
+
+    public function testGetInstantiatesClassWithConstructorAndUsesArguments(): void
+    {
+        $classWithConstructor = Foo::class;
+        $dependencyClass = Bar::class;
+
+        $dependency = new $dependencyClass();
+        $container = new ReflectionContainer();
+
+        $item = $container->get($classWithConstructor, [
+            'bar' => $dependency,
+        ]);
+
+        self::assertInstanceOf($classWithConstructor, $item);
+        self::assertSame($dependency, $item->bar);
+    }
+
+    public function testThrowsWhenGettingNonExistentClass(): void
+    {
+        $this->expectException(NotFoundException::class);
+        $container = new ReflectionContainer();
+        $container->get('Whoooo');
+    }
+
+    public function testCallReflectsOnClosureArguments(): void
+    {
+        $container = new ReflectionContainer();
+
+        $foo = $container->call(function (Foo $foo) {
+            return $foo;
+        });
+
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+    }
+
+    public function testCallReflectsOnInstanceMethodArguments(): void
+    {
+        $container = new ReflectionContainer();
+        $foo = new Foo();
+        $container->call($foo->setBar(...));
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+    }
+
+    public function testCallReflectsOnStaticMethodArguments(): void
+    {
+        $container = new ReflectionContainer();
+        $container->call('Cake\Test\TestCase\Container\Asset\Foo::staticSetBar');
+        self::assertInstanceOf(Bar::class, Asset\Foo::$staticBar);
+        self::assertEquals('hello world', Asset\Foo::$staticHello);
+    }
+
+    public function testCallThrowsWhenArgumentCannotBeResolved(): void
+    {
+        $this->expectException(NotFoundException::class);
+        $container = new ReflectionContainer();
+        $container->call([new Bar(), 'setSomething']);
+    }
+
+    public function testCallResolvesInvokableClass(): void
+    {
+        $container = new ReflectionContainer();
+        $foo = $container->call(new FooCallable(), [new Bar()]);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+    }
+
+    public function testCallResolvesFunction(): void
+    {
+        $container = new ReflectionContainer();
+        $foo = $container->call('\Cake\Test\TestCase\Container\Asset\test', [new Bar()]);
+        self::assertInstanceOf(Foo::class, $foo);
+        self::assertInstanceOf(Bar::class, $foo->bar);
+    }
+
+    public function testCallThrowsOnUnknownString(): void
+    {
+        $container = new ReflectionContainer();
+        $this->expectException(NotFoundException::class);
+        $this->expectExceptionMessage('Callable (Unknown) is not a valid callable');
+        $container->call('Unknown', [new Bar()]);
+    }
+
+    public function testGetInstantiatesClassWithConstructorAndSkipsProtectedConstructor(): void
+    {
+        $classWithConstructor = ProFoo::class;
+
+        $container = new Container();
+        $container->delegate(new ReflectionContainer());
+
+        $item = $container->get($classWithConstructor);
+
+        $this->assertInstanceOf($classWithConstructor, $item);
+        $this->assertNull($item->bar);
+    }
+
+    public function testGetInstantiatesClassWithConstructorAndUsesFactory(): void
+    {
+        $classWithConstructor = ProFoo::class;
+        $dependencyClass = ProBar::class;
+
+        $container = new Container();
+        $container->delegate(new ReflectionContainer());
+
+        $container->add($dependencyClass, [$dependencyClass, 'factory']);
+
+        $item = $container->get($classWithConstructor);
+
+        $this->assertInstanceOf($classWithConstructor, $item);
+        $this->assertInstanceOf($dependencyClass, $item->bar);
+    }
+}
diff --git a/tests/TestCase/Container/ServiceProvider/ServiceProviderAggregateTest.php b/tests/TestCase/Container/ServiceProvider/ServiceProviderAggregateTest.php
new file mode 100644
index 00000000000..dafbf1b92a2
--- /dev/null
+++ b/tests/TestCase/Container/ServiceProvider/ServiceProviderAggregateTest.php
@@ -0,0 +1,92 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\ServiceProvider;
+
+use Cake\Container\Container;
+use Cake\Container\Exception\ContainerException;
+use Cake\Container\ServiceProvider\AbstractServiceProvider;
+use Cake\Container\ServiceProvider\BootableServiceProviderInterface;
+use Cake\Container\ServiceProvider\ServiceProviderAggregate;
+use Cake\Container\ServiceProvider\ServiceProviderInterface;
+use PHPUnit\Framework\TestCase;
+
+class ServiceProviderAggregateTest extends TestCase
+{
+    protected function getServiceProvider(): ServiceProviderInterface
+    {
+        return new class extends AbstractServiceProvider implements BootableServiceProviderInterface {
+            public $booted = 0;
+            public $registered = 0;
+
+            public function provides(string $id): bool
+            {
+                return in_array($id, [
+                    'SomeService',
+                    'AnotherService',
+                ], true);
+            }
+
+            public function boot(): void
+            {
+                $this->booted++;
+            }
+
+            public function register(): void
+            {
+                $this->registered++;
+
+                $this->getContainer()->add('SomeService', function ($arg) {
+                    return $arg;
+                });
+            }
+        };
+    }
+
+    public function testAggregateAddsClassNameServiceProvider(): void
+    {
+        $container = new Container();
+        $aggregate = new ServiceProviderAggregate();
+        $aggregate->setContainer($container);
+        $aggregate->add($this->getServiceProvider());
+        self::assertTrue($aggregate->provides('SomeService'));
+        self::assertTrue($aggregate->provides('AnotherService'));
+    }
+
+    public function testAggregateThrowsWhenRegisteringForServiceThatIsNotAdded(): void
+    {
+        $this->expectException(ContainerException::class);
+        $container = new Container();
+        $aggregate = (new ServiceProviderAggregate())->setContainer($container);
+        $aggregate->register('SomeService');
+    }
+
+    public function testAggregateInvokesCorrectRegisterMethodOnlyOnce(): void
+    {
+        $container = new Container();
+        $aggregate = (new ServiceProviderAggregate())->setContainer($container);
+        $provider = $this->getServiceProvider();
+        $aggregate->add($provider);
+        $aggregate->register('SomeService');
+        $aggregate->register('AnotherService');
+        self::assertSame(1, $provider->registered);
+    }
+
+    public function testAggregateSkipsExistingProviders(): void
+    {
+        $container = new Container();
+        $aggregate = (new ServiceProviderAggregate())->setContainer($container);
+        $provider = $this->getServiceProvider();
+        $aggregate->add($provider);
+        $aggregate->add($provider);
+
+        // assert after adding provider multiple times, that it
+        // was only aggregated and booted once
+        self::assertSame(
+            [$provider],
+            iterator_to_array($aggregate->getIterator()),
+        );
+
+        self::assertSame(1, $provider->booted);
+    }
+}
diff --git a/tests/TestCase/Container/ServiceProvider/ServiceProviderTest.php b/tests/TestCase/Container/ServiceProvider/ServiceProviderTest.php
new file mode 100644
index 00000000000..8d6c8f43e73
--- /dev/null
+++ b/tests/TestCase/Container/ServiceProvider/ServiceProviderTest.php
@@ -0,0 +1,45 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Container\ServiceProvider;
+
+use Cake\Container\ServiceProvider\AbstractServiceProvider;
+use Cake\Container\ServiceProvider\BootableServiceProviderInterface;
+use Cake\Container\ServiceProvider\ServiceProviderInterface;
+use PHPUnit\Framework\TestCase;
+
+class ServiceProviderTest extends TestCase
+{
+    protected function getServiceProvider(): ServiceProviderInterface
+    {
+        return new class extends AbstractServiceProvider implements BootableServiceProviderInterface
+        {
+            public function provides(string $id): bool
+            {
+                return in_array($id, [
+                    'SomeService',
+                    'AnotherService',
+                ], true);
+            }
+
+            public function boot(): void
+            {
+            }
+
+            public function register(): void
+            {
+                $this->getContainer()->add('SomeService', function ($arg) {
+                    return $arg;
+                });
+            }
+        };
+    }
+
+    public function testServiceProviderCorrectlyDeterminesWhatIsProvided(): void
+    {
+        $provider = $this->getServiceProvider()->setIdentifier('something');
+        self::assertTrue($provider->provides('SomeService'));
+        self::assertTrue($provider->provides('AnotherService'));
+        self::assertFalse($provider->provides('NonService'));
+    }
+}
diff --git a/tests/TestCase/Controller/Component/FormProtectionComponentTest.php b/tests/TestCase/Controller/Component/FormProtectionComponentTest.php
index ce48e4459ca..31b27b95ee9 100644
--- a/tests/TestCase/Controller/Component/FormProtectionComponentTest.php
+++ b/tests/TestCase/Controller/Component/FormProtectionComponentTest.php
@@ -329,4 +329,40 @@ public function testClearingOfTokenFromRequestData(): void
 
         $this->assertSame([], $this->Controller->getRequest()->getParsedBody());
     }
+
+    /**
+     * Test unlockActions() method.
+     */
+    public function testUnlockActions(): void
+    {
+        // Single action as string
+        $this->FormProtection->unlockActions('index');
+        $this->assertSame(['index'], $this->FormProtection->getConfig('unlockedActions'));
+
+        // Multiple actions as array, merges by default
+        $this->FormProtection->unlockActions(['view', 'add']);
+        $this->assertSame(['index', 'view', 'add'], $this->FormProtection->getConfig('unlockedActions'));
+
+        // Replace when merge is false
+        $this->FormProtection->unlockActions('edit', false);
+        $this->assertSame(['edit'], $this->FormProtection->getConfig('unlockedActions'));
+    }
+
+    /**
+     * Test unlockFields() method.
+     */
+    public function testUnlockFields(): void
+    {
+        // Single field as string
+        $this->FormProtection->unlockFields('csrf_token');
+        $this->assertSame(['csrf_token'], $this->FormProtection->getConfig('unlockedFields'));
+
+        // Multiple fields as array, merges by default
+        $this->FormProtection->unlockFields(['debug', 'dynamic_field']);
+        $this->assertSame(['csrf_token', 'debug', 'dynamic_field'], $this->FormProtection->getConfig('unlockedFields'));
+
+        // Replace when merge is false
+        $this->FormProtection->unlockFields('new_field', false);
+        $this->assertSame(['new_field'], $this->FormProtection->getConfig('unlockedFields'));
+    }
 }
diff --git a/tests/TestCase/Controller/ControllerFactoryTest.php b/tests/TestCase/Controller/ControllerFactoryTest.php
index dd9aa90620f..de2579702c7 100644
--- a/tests/TestCase/Controller/ControllerFactoryTest.php
+++ b/tests/TestCase/Controller/ControllerFactoryTest.php
@@ -562,6 +562,108 @@ public function testInvokeInjectParametersRequiredNotDefined(): void
         $this->factory->invoke($controller);
     }
 
+    public function testInvokeRequestToDtoAttribute(): void
+    {
+        $request = new ServerRequest([
+            'url' => 'dependencies/requestDto',
+            'params' => [
+                'plugin' => null,
+                'controller' => 'Dependencies',
+                'action' => 'requestDto',
+            ],
+            'post' => [
+                'title' => 'Map Request',
+                'count' => '3',
+            ],
+            'environment' => [
+                'REQUEST_METHOD' => 'POST',
+            ],
+        ]);
+        $controller = $this->factory->create($request);
+        $result = $this->factory->invoke($controller);
+        $data = json_decode((string)$result->getBody(), true);
+
+        $this->assertSame(['title' => 'Map Request', 'count' => '3'], $data);
+    }
+
+    public function testInvokeRequestToDtoBodySource(): void
+    {
+        $request = new ServerRequest([
+            'url' => 'dependencies/requestDtoBody',
+            'params' => [
+                'plugin' => null,
+                'controller' => 'Dependencies',
+                'action' => 'requestDtoBody',
+            ],
+            'post' => [
+                'title' => 'Body Data',
+            ],
+            'query' => [
+                'ignored' => 'query param',
+            ],
+            'environment' => [
+                'REQUEST_METHOD' => 'POST',
+            ],
+        ]);
+        $controller = $this->factory->create($request);
+        $result = $this->factory->invoke($controller);
+        $data = json_decode((string)$result->getBody(), true);
+
+        $this->assertSame(['title' => 'Body Data'], $data);
+    }
+
+    public function testInvokeRequestToDtoQuerySource(): void
+    {
+        $request = new ServerRequest([
+            'url' => 'dependencies/requestDtoQuery',
+            'params' => [
+                'plugin' => null,
+                'controller' => 'Dependencies',
+                'action' => 'requestDtoQuery',
+            ],
+            'post' => [
+                'ignored' => 'post data',
+            ],
+            'query' => [
+                'search' => 'query value',
+            ],
+            'environment' => [
+                'REQUEST_METHOD' => 'POST',
+            ],
+        ]);
+        $controller = $this->factory->create($request);
+        $result = $this->factory->invoke($controller);
+        $data = json_decode((string)$result->getBody(), true);
+
+        $this->assertSame(['search' => 'query value'], $data);
+    }
+
+    public function testInvokeRequestToDtoRequestSource(): void
+    {
+        $request = new ServerRequest([
+            'url' => 'dependencies/requestDtoRequest',
+            'params' => [
+                'plugin' => null,
+                'controller' => 'Dependencies',
+                'action' => 'requestDtoRequest',
+            ],
+            'post' => [
+                'title' => 'Post Title',
+            ],
+            'query' => [
+                'page' => '2',
+            ],
+            'environment' => [
+                'REQUEST_METHOD' => 'POST',
+            ],
+        ]);
+        $controller = $this->factory->create($request);
+        $result = $this->factory->invoke($controller);
+        $data = json_decode((string)$result->getBody(), true);
+
+        $this->assertSame(['page' => '2', 'title' => 'Post Title'], $data);
+    }
+
     public function testInvokeInjectParametersRequiredMissingUntyped(): void
     {
         $request = new ServerRequest([
diff --git a/tests/TestCase/Controller/ControllerTest.php b/tests/TestCase/Controller/ControllerTest.php
index ae0ba677833..8007145b336 100644
--- a/tests/TestCase/Controller/ControllerTest.php
+++ b/tests/TestCase/Controller/ControllerTest.php
@@ -1010,6 +1010,22 @@ public function testLoadComponentWithContainer(): void
         $this->assertTrue(isset($registry->Flash));
     }
 
+    /**
+     * Test that loading a component with the same name as defaultTable triggers a warning.
+     */
+    public function testLoadComponentNameClashWithDefaultTable(): void
+    {
+        $request = new ServerRequest(['url' => '/']);
+        $controller = new WithDefaultTableController($request);
+
+        $this->expectWarningMessageMatches(
+            '/Component alias `Posts` clashes with the default table name `Posts`/',
+            function () use ($controller): void {
+                $controller->loadComponent('Posts');
+            },
+        );
+    }
+
     /**
      * Test the isAction method.
      */
diff --git a/tests/TestCase/Core/PluginConfigTest.php b/tests/TestCase/Core/PluginConfigTest.php
index 7d9c94d841e..afbf2b06491 100644
--- a/tests/TestCase/Core/PluginConfigTest.php
+++ b/tests/TestCase/Core/PluginConfigTest.php
@@ -53,6 +53,7 @@ protected function tearDown(): void
     {
         parent::tearDown();
         Configure::delete('plugins');
+        PluginConfig::clearCache();
         $this->clearPlugins();
         if (file_exists($this->pluginsListPath)) {
             unlink($this->pluginsListPath);
@@ -390,4 +391,182 @@ public function testInvalidComposerJson(): void
         ], PluginConfig::getAppConfig());
         unlink($pathToTestPlugin . 'composer.json');
     }
+
+    public function testGetInstalledPluginsSimple(): void
+    {
+        $file = <<<PHP
+<?php
+return [
+    'plugins' => [
+        'TestPlugin' => '/config/path/',
+        'OtherPlugin' => '/other/path/',
+    ]
+];
+PHP;
+        file_put_contents($this->pluginsListPath, $file);
+
+        $config = <<<PHP
+<?php
+return [
+    'TestPlugin',
+];
+PHP;
+        file_put_contents($this->pluginsConfigPath, $config);
+
+        Configure::delete('plugins');
+        $result = PluginConfig::getInstalledPlugins();
+
+        $expected = [
+            'TestPlugin' => [
+                'path' => '/config/path/',
+                'isLoaded' => true,
+                'onlyDebug' => false,
+                'onlyCli' => false,
+                'optional' => false,
+                'bootstrap' => true,
+                'console' => true,
+                'middleware' => true,
+                'routes' => true,
+                'services' => true,
+                'events' => true,
+            ],
+            'OtherPlugin' => [
+                'path' => '/other/path/',
+                'isLoaded' => false,
+            ],
+        ];
+        $this->assertSame($expected, $result);
+    }
+
+    public function testGetInstalledPluginsWithOptions(): void
+    {
+        $file = <<<PHP
+<?php
+return [
+    'plugins' => [
+        'DebugPlugin' => '/debug/path/',
+        'CliPlugin' => '/cli/path/',
+        'OptionalPlugin' => '/optional/path/',
+    ]
+];
+PHP;
+        file_put_contents($this->pluginsListPath, $file);
+
+        $config = <<<PHP
+<?php
+return [
+    'DebugPlugin' => ['onlyDebug' => true],
+    'CliPlugin' => ['onlyCli' => true],
+    'OptionalPlugin' => ['optional' => true, 'bootstrap' => false],
+];
+PHP;
+        file_put_contents($this->pluginsConfigPath, $config);
+
+        Configure::delete('plugins');
+        $result = PluginConfig::getInstalledPlugins();
+
+        $expected = [
+            'DebugPlugin' => [
+                'path' => '/debug/path/',
+                'isLoaded' => true,
+                'onlyDebug' => true,
+                'onlyCli' => false,
+                'optional' => false,
+                'bootstrap' => true,
+                'console' => true,
+                'middleware' => true,
+                'routes' => true,
+                'services' => true,
+                'events' => true,
+            ],
+            'CliPlugin' => [
+                'path' => '/cli/path/',
+                'isLoaded' => true,
+                'onlyDebug' => false,
+                'onlyCli' => true,
+                'optional' => false,
+                'bootstrap' => true,
+                'console' => true,
+                'middleware' => true,
+                'routes' => true,
+                'services' => true,
+                'events' => true,
+            ],
+            'OptionalPlugin' => [
+                'path' => '/optional/path/',
+                'isLoaded' => true,
+                'onlyDebug' => false,
+                'onlyCli' => false,
+                'optional' => true,
+                'bootstrap' => false,
+                'console' => true,
+                'middleware' => true,
+                'routes' => true,
+                'services' => true,
+                'events' => true,
+            ],
+        ];
+        $this->assertSame($expected, $result);
+    }
+
+    public function testGetInstalledPluginsNoPluginsConfig(): void
+    {
+        $file = <<<PHP
+<?php
+return [
+    'plugins' => [
+        'TestPlugin' => '/test/path/',
+    ]
+];
+PHP;
+        file_put_contents($this->pluginsListPath, $file);
+
+        // Delete plugins.php to test fallback
+        if (file_exists($this->pluginsConfigPath)) {
+            unlink($this->pluginsConfigPath);
+        }
+
+        Configure::delete('plugins');
+        $result = PluginConfig::getInstalledPlugins();
+
+        $expected = [
+            'TestPlugin' => [
+                'path' => '/test/path/',
+                'isLoaded' => false,
+            ],
+        ];
+        $this->assertSame($expected, $result);
+    }
+
+    public function testGetInstalledPluginsUnknownPlugin(): void
+    {
+        $file = <<<PHP
+<?php
+return [
+    'plugins' => [
+        'TestPlugin' => '/test/path/',
+    ]
+];
+PHP;
+        file_put_contents($this->pluginsListPath, $file);
+
+        $config = <<<PHP
+<?php
+return [
+    'TestPlugin',
+    'UnknownPlugin',
+];
+PHP;
+        file_put_contents($this->pluginsConfigPath, $config);
+
+        Configure::delete('plugins');
+        $result = PluginConfig::getInstalledPlugins();
+
+        $this->assertArrayHasKey('TestPlugin', $result);
+        $this->assertArrayHasKey('UnknownPlugin', $result);
+        $this->assertTrue($result['TestPlugin']['isLoaded']);
+        $this->assertFalse($result['UnknownPlugin']['isLoaded']);
+        $this->assertTrue($result['UnknownPlugin']['isUnknown']);
+        $this->assertArrayNotHasKey('path', $result['UnknownPlugin']);
+    }
 }
diff --git a/tests/TestCase/Database/ConnectionTest.php b/tests/TestCase/Database/ConnectionTest.php
index da6e9abda00..6ac56969404 100644
--- a/tests/TestCase/Database/ConnectionTest.php
+++ b/tests/TestCase/Database/ConnectionTest.php
@@ -42,6 +42,7 @@
 use Psr\Log\AbstractLogger;
 use ReflectionMethod;
 use ReflectionProperty;
+use RuntimeException;
 use TestApp\Database\Driver\DisabledDriver;
 use TestApp\Database\Driver\RetryDriver;
 use TestApp\Database\Driver\StubDriver;
@@ -1286,4 +1287,126 @@ public function testRoleConfigInheritance(): void
         $this->assertSame('write.db', $writeDriver->config()['database'], 'Write database should be overridden.');
         $this->assertSame('default-user', $writeDriver->config()['username'], 'Write username should be inherited.');
     }
+
+    public function testAfterCommitCallbackFiredOnCommit(): void
+    {
+        $fired = false;
+        $this->connection->begin();
+        $this->connection->afterCommit(function () use (&$fired): void {
+            $fired = true;
+        });
+        $this->assertFalse($fired);
+        $this->connection->commit();
+        $this->assertTrue($fired);
+    }
+
+    public function testAfterCommitCallbackDiscardedOnRollback(): void
+    {
+        $fired = false;
+        $this->connection->begin();
+        $this->connection->afterCommit(function () use (&$fired): void {
+            $fired = true;
+        });
+        $this->connection->rollback();
+        $this->assertFalse($fired);
+
+        // Verify callback doesn't leak into subsequent transaction
+        $this->connection->begin();
+        $this->connection->commit();
+        $this->assertFalse($fired);
+    }
+
+    public function testAfterCommitExecutesImmediatelyOutsideTransaction(): void
+    {
+        $fired = false;
+        $this->connection->afterCommit(function () use (&$fired): void {
+            $fired = true;
+        });
+        $this->assertTrue($fired);
+    }
+
+    public function testAfterCommitCallbacksFireInRegistrationOrder(): void
+    {
+        $order = [];
+        $this->connection->begin();
+        $this->connection->afterCommit(function () use (&$order): void {
+            $order[] = 'first';
+        });
+        $this->connection->afterCommit(function () use (&$order): void {
+            $order[] = 'second';
+        });
+        $this->connection->commit();
+        $this->assertSame(['first', 'second'], $order);
+    }
+
+    public function testAfterCommitCallbacksFiredAfterNestedCommit(): void
+    {
+        $firedOuter = false;
+        $firedInner = false;
+        $this->connection->begin();
+        $this->connection->afterCommit(function () use (&$firedOuter): void {
+            $firedOuter = true;
+        });
+        $this->connection->begin(); // nested
+        $this->connection->afterCommit(function () use (&$firedInner): void {
+            $firedInner = true;
+        });
+        $this->connection->commit(); // commit nested
+        $this->assertFalse($firedOuter, 'Outer callback must not fire until outermost commit');
+        $this->assertFalse($firedInner, 'Inner callback must not fire until outermost commit');
+        $this->connection->commit(); // commit outermost
+        $this->assertTrue($firedOuter);
+        $this->assertTrue($firedInner);
+    }
+
+    public function testAfterCommitCallbacksDiscardedOnNestedRollbackToBeginning(): void
+    {
+        $fired = false;
+        $this->connection->begin();
+        $this->connection->begin(); // nested — savepoint
+        $this->connection->afterCommit(function () use (&$fired): void {
+            $fired = true;
+        });
+        $this->connection->rollback(true); // rollback to beginning
+        $this->assertFalse($fired);
+    }
+
+    public function testAfterCommitCallbacksSurviveSavepointRollback(): void
+    {
+        $this->connection->enableSavePoints();
+        $this->skipIf(!$this->connection->isSavePointsEnabled(), 'Driver does not support save points');
+
+        $firedA = false;
+        $firedB = false;
+        $this->connection->begin();
+        $this->connection->afterCommit(function () use (&$firedA): void {
+            $firedA = true;
+        });
+        $this->connection->begin(); // savepoint
+        $this->connection->afterCommit(function () use (&$firedB): void {
+            $firedB = true;
+        });
+        $this->connection->rollback(); // rollback savepoint only
+        $this->connection->commit(); // commit outermost
+        $this->assertTrue($firedA);
+        $this->assertTrue($firedB);
+    }
+
+    public function testAfterCommitCallbackExceptionStopsExecution(): void
+    {
+        $secondFired = false;
+        $this->connection->begin();
+        $this->connection->afterCommit(function (): void {
+            throw new RuntimeException('callback failed');
+        });
+        $this->connection->afterCommit(function () use (&$secondFired): void {
+            $secondFired = true;
+        });
+        try {
+            $this->connection->commit();
+        } catch (RuntimeException) {
+            // Expected
+        }
+        $this->assertFalse($secondFired, 'Remaining callbacks should not execute when one throws');
+    }
 }
diff --git a/tests/TestCase/Database/Driver/MysqlTest.php b/tests/TestCase/Database/Driver/MysqlTest.php
index 0b4e094b14a..a268b968a6d 100644
--- a/tests/TestCase/Database/Driver/MysqlTest.php
+++ b/tests/TestCase/Database/Driver/MysqlTest.php
@@ -16,14 +16,17 @@
  */
 namespace Cake\Test\TestCase\Database\Driver;
 
+use Cake\Database\Connection;
 use Cake\Database\Driver\Mysql;
 use Cake\Database\DriverFeatureEnum;
+use Cake\Database\Query\SelectQuery;
 use Cake\Datasource\ConnectionManager;
 use Cake\TestSuite\TestCase;
 use Mockery;
 use PDO;
 use Pdo\Mysql as PdoMysql;
 use PHPUnit\Framework\Attributes\DataProvider;
+use ReflectionClass;
 
 /**
  * Tests MySQL driver
@@ -220,15 +223,21 @@ public function testSupports(): void
                 'json' => '5.7.0',
                 'cte' => '8.0.0',
                 'window' => '8.0.0',
+                'string-agg' => '99.0.0',
                 'intersect' => '8.0.31',
                 'intersect-all' => '8.0.31',
+                'except' => '8.0.31',
+                'except-all' => '8.0.31',
             ],
             'mariadb' => [
                 'json' => '10.2.7',
                 'cte' => '10.2.1',
                 'window' => '10.2.0',
+                'string-agg' => '10.5.0',
                 'intersect' => '10.3.0',
                 'intersect-all' => '10.5.0',
+                'except' => '10.3.0',
+                'except-all' => '10.5.0',
             ],
         ];
         foreach ($featureVersions[$serverType] as $feature => $version) {
@@ -240,10 +249,66 @@ public function testSupports(): void
 
         $this->assertTrue($driver->supports(DriverFeatureEnum::DISABLE_CONSTRAINT_WITHOUT_TRANSACTION));
         $this->assertTrue($driver->supports(DriverFeatureEnum::SAVEPOINT));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::GROUP_CONCAT));
 
         $this->assertFalse($driver->supports(DriverFeatureEnum::TRUNCATE_WITH_CONSTRAINTS));
     }
 
+    /**
+     * Tests string aggregation translation for MySQL.
+     */
+    public function testStringAggTranslationForMysql(): void
+    {
+        $driver = Mockery::mock(Mysql::class)
+            ->makePartial()
+            ->shouldAllowMockingProtectedMethods();
+        $driver->__construct([]);
+        $driver->shouldReceive('enabled')->andReturn(true);
+        $driver->shouldReceive('connect')->andReturnNull();
+        $driver->shouldReceive('getPdo')->andReturn(Mockery::mock(PDO::class));
+        $driver->shouldReceive('version')->andReturn('8.4.0');
+
+        $connection = new Connection(['driver' => $driver, 'log' => false]);
+        $query = new SelectQuery($connection);
+        $query->select([
+            'names' => $query->func()->stringAgg('name', ',', ['sort_order' => 'DESC']),
+        ])->from('authors');
+
+        $this->assertSame(
+            'SELECT (GROUP_CONCAT(name ORDER BY sort_order DESC SEPARATOR :param0)) AS names FROM authors',
+            $query->sql(),
+        );
+    }
+
+    /**
+     * Tests string aggregation translation for MariaDB.
+     */
+    public function testStringAggTranslationForMariadb(): void
+    {
+        $driver = Mockery::mock(Mysql::class)
+            ->makePartial()
+            ->shouldAllowMockingProtectedMethods();
+        $driver->__construct([]);
+        $reflection = new ReflectionClass($driver);
+        $serverType = $reflection->getProperty('serverType');
+        $serverType->setValue($driver, 'mariadb');
+        $driver->shouldReceive('enabled')->andReturn(true);
+        $driver->shouldReceive('connect')->andReturnNull();
+        $driver->shouldReceive('getPdo')->andReturn(Mockery::mock(PDO::class));
+        $driver->shouldReceive('version')->andReturn('10.5.0');
+
+        $connection = new Connection(['driver' => $driver, 'log' => false]);
+        $query = new SelectQuery($connection);
+        $query->select([
+            'names' => $query->func()->stringAgg('name', ',', ['sort_order' => 'DESC']),
+        ])->from('authors');
+
+        $this->assertSame(
+            'SELECT (STRING_AGG(name, :param0 ORDER BY sort_order DESC)) AS names FROM authors',
+            $query->sql(),
+        );
+    }
+
     /**
      * Tests identifier quoting
      */
diff --git a/tests/TestCase/Database/Driver/PostgresTest.php b/tests/TestCase/Database/Driver/PostgresTest.php
index 47a2465caed..5f9bdf2034e 100644
--- a/tests/TestCase/Database/Driver/PostgresTest.php
+++ b/tests/TestCase/Database/Driver/PostgresTest.php
@@ -222,6 +222,32 @@ public function testHavingWhenNoAliasIsUsed(): void
         $this->assertSame($expected, $query->sql());
     }
 
+    /**
+     * Tests string aggregation translation.
+     */
+    public function testStringAggTranslation(): void
+    {
+        $driver = Mockery::mock(Postgres::class)
+            ->makePartial()
+            ->shouldAllowMockingProtectedMethods();
+        $driver->__construct([]);
+        $driver->shouldReceive('enabled')->andReturn(true);
+        $driver->shouldReceive('connect')->andReturnNull();
+        $driver->shouldReceive('getPdo')->andReturn(Mockery::mock(PDO::class));
+        $driver->shouldReceive('version')->andReturn('16.0');
+
+        $connection = new Connection(['driver' => $driver, 'log' => false]);
+        $query = new SelectQuery($connection);
+        $query->select([
+            'names' => $query->func()->stringAgg('name', ',', ['sort_order' => 'DESC']),
+        ])->from('authors');
+
+        $this->assertSame(
+            'SELECT (STRING_AGG(name, :param0 ORDER BY sort_order DESC)) AS "names" FROM authors',
+            $query->sql(),
+        );
+    }
+
     /**
      * Tests driver-specific feature support check.
      */
@@ -235,8 +261,12 @@ public function testSupports(): void
         $this->assertTrue($driver->supports(DriverFeatureEnum::SAVEPOINT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::TRUNCATE_WITH_CONSTRAINTS));
         $this->assertTrue($driver->supports(DriverFeatureEnum::WINDOW));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::STRING_AGG));
+        $this->assertFalse($driver->supports(DriverFeatureEnum::GROUP_CONCAT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::INTERSECT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::INTERSECT_ALL));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::EXCEPT));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::EXCEPT_ALL));
         $this->assertTrue($driver->supports(DriverFeatureEnum::SET_OPERATIONS_ORDER_BY));
 
         $this->assertFalse($driver->supports(DriverFeatureEnum::DISABLE_CONSTRAINT_WITHOUT_TRANSACTION));
diff --git a/tests/TestCase/Database/Driver/SqliteTest.php b/tests/TestCase/Database/Driver/SqliteTest.php
index 146dac7252e..55f5d479b31 100644
--- a/tests/TestCase/Database/Driver/SqliteTest.php
+++ b/tests/TestCase/Database/Driver/SqliteTest.php
@@ -20,6 +20,7 @@
 use Cake\Database\Connection;
 use Cake\Database\Driver\Sqlite;
 use Cake\Database\DriverFeatureEnum;
+use Cake\Database\Query\SelectQuery;
 use Cake\Datasource\ConnectionManager;
 use Cake\TestSuite\TestCase;
 use Mockery;
@@ -202,6 +203,7 @@ public function testSupports(): void
 
         $featureVersions = [
             'cte' => '3.8.3',
+            'string-agg' => '3.44.0',
             'window' => '3.28.0',
         ];
         foreach ($featureVersions as $feature => $version) {
@@ -214,13 +216,42 @@ public function testSupports(): void
         $this->assertTrue($driver->supports(DriverFeatureEnum::DISABLE_CONSTRAINT_WITHOUT_TRANSACTION));
         $this->assertTrue($driver->supports(DriverFeatureEnum::SAVEPOINT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::TRUNCATE_WITH_CONSTRAINTS));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::GROUP_CONCAT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::INTERSECT));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::EXCEPT));
 
         $this->assertFalse($driver->supports(DriverFeatureEnum::INTERSECT_ALL));
+        $this->assertFalse($driver->supports(DriverFeatureEnum::EXCEPT_ALL));
         $this->assertFalse($driver->supports(DriverFeatureEnum::JSON));
         $this->assertFalse($driver->supports(DriverFeatureEnum::SET_OPERATIONS_ORDER_BY));
     }
 
+    /**
+     * Tests string aggregation translation.
+     */
+    public function testStringAggTranslation(): void
+    {
+        $driver = Mockery::mock(Sqlite::class)
+            ->makePartial()
+            ->shouldAllowMockingProtectedMethods();
+        $driver->__construct([]);
+        $driver->shouldReceive('enabled')->andReturn(true);
+        $driver->shouldReceive('connect')->andReturnNull();
+        $driver->shouldReceive('getPdo')->andReturn(Mockery::mock(PDO::class));
+        $driver->shouldReceive('version')->andReturn('3.43.0');
+
+        $connection = new Connection(['driver' => $driver, 'log' => false]);
+        $query = new SelectQuery($connection);
+        $query->select([
+            'names' => $query->func()->stringAgg('name', ',', ['sort_order' => 'DESC']),
+        ])->from('authors');
+
+        $this->assertSame(
+            'SELECT (GROUP_CONCAT(name, :param0 ORDER BY sort_order DESC)) AS names FROM authors',
+            $query->sql(),
+        );
+    }
+
     /**
      * Test of Inconsistency for JSON type field between mysql and sqlite
      *
diff --git a/tests/TestCase/Database/Driver/SqlserverTest.php b/tests/TestCase/Database/Driver/SqlserverTest.php
index cc399ce262d..fde58ef7dcd 100644
--- a/tests/TestCase/Database/Driver/SqlserverTest.php
+++ b/tests/TestCase/Database/Driver/SqlserverTest.php
@@ -532,6 +532,32 @@ public function testHavingWhenNoAliasIsUsed(): void
         $this->assertSame($expected, $query->sql());
     }
 
+    /**
+     * Tests string aggregation translation.
+     */
+    public function testStringAggTranslation(): void
+    {
+        $driver = Mockery::mock(Sqlserver::class)
+            ->makePartial()
+            ->shouldAllowMockingProtectedMethods();
+        $driver->__construct([]);
+        $driver->shouldReceive('version')->andReturn('16');
+        $driver->shouldReceive('enabled')->andReturn(true);
+        $driver->shouldReceive('connect')->andReturnNull();
+        $driver->shouldReceive('getPdo')->andReturn(Mockery::mock(PDO::class));
+
+        $connection = new Connection(['driver' => $driver, 'log' => false]);
+        $query = new SelectQuery($connection);
+        $query->select([
+            'names' => $query->func()->stringAgg('name', ',', ['sort_order' => 'DESC']),
+        ])->from('authors');
+
+        $this->assertSame(
+            'SELECT (STRING_AGG(name, :param0) WITHIN GROUP (ORDER BY sort_order DESC)) AS names FROM authors',
+            $query->sql(),
+        );
+    }
+
     public function testExceedingMaxParameters(): void
     {
         $connection = ConnectionManager::get('test');
@@ -561,9 +587,13 @@ public function testSupports(): void
         $this->assertTrue($driver->supports(DriverFeatureEnum::SAVEPOINT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::TRUNCATE_WITH_CONSTRAINTS));
         $this->assertTrue($driver->supports(DriverFeatureEnum::WINDOW));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::STRING_AGG));
+        $this->assertFalse($driver->supports(DriverFeatureEnum::GROUP_CONCAT));
         $this->assertTrue($driver->supports(DriverFeatureEnum::INTERSECT));
+        $this->assertTrue($driver->supports(DriverFeatureEnum::EXCEPT));
 
         $this->assertFalse($driver->supports(DriverFeatureEnum::INTERSECT_ALL));
+        $this->assertFalse($driver->supports(DriverFeatureEnum::EXCEPT_ALL));
         $this->assertFalse($driver->supports(DriverFeatureEnum::JSON));
         $this->assertFalse($driver->supports(DriverFeatureEnum::SET_OPERATIONS_ORDER_BY));
     }
diff --git a/tests/TestCase/Database/Expression/BetweenExpressionTest.php b/tests/TestCase/Database/Expression/BetweenExpressionTest.php
new file mode 100644
index 00000000000..100110994a3
--- /dev/null
+++ b/tests/TestCase/Database/Expression/BetweenExpressionTest.php
@@ -0,0 +1,100 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Database\Expression;
+
+use Cake\Database\Expression\BetweenExpression;
+use Cake\Database\Expression\IdentifierExpression;
+use Cake\Database\ValueBinder;
+use Cake\TestSuite\TestCase;
+
+/**
+ * Tests BetweenExpression class
+ */
+class BetweenExpressionTest extends TestCase
+{
+    /**
+     * Tests that BETWEEN expression is generated correctly
+     */
+    public function testBetween(): void
+    {
+        $expr = new BetweenExpression('age', 18, 65);
+        $this->assertEqualsSql(
+            'age BETWEEN :c0 AND :c1',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests that NOT BETWEEN expression is generated correctly
+     */
+    public function testNotBetween(): void
+    {
+        $expr = new BetweenExpression('age', 18, 65, null, true);
+        $this->assertEqualsSql(
+            'age NOT BETWEEN :c0 AND :c1',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests BETWEEN with an identifier expression as field
+     */
+    public function testBetweenWithIdentifierField(): void
+    {
+        $expr = new BetweenExpression(
+            new IdentifierExpression('Users.age'),
+            18,
+            65,
+        );
+        $this->assertEqualsSql(
+            'Users.age BETWEEN :c0 AND :c1',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests NOT BETWEEN with an identifier expression as field
+     */
+    public function testNotBetweenWithIdentifierField(): void
+    {
+        $expr = new BetweenExpression(
+            new IdentifierExpression('Users.age'),
+            18,
+            65,
+            null,
+            true,
+        );
+        $this->assertEqualsSql(
+            'Users.age NOT BETWEEN :c0 AND :c1',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests that values are properly bound with type
+     */
+    public function testBetweenWithType(): void
+    {
+        $expr = new BetweenExpression('score', 10, 100, 'integer');
+        $binder = new ValueBinder();
+        $expr->sql($binder);
+
+        $bindings = $binder->bindings();
+        $this->assertSame('integer', $bindings[':c0']['type']);
+        $this->assertSame('integer', $bindings[':c1']['type']);
+    }
+}
diff --git a/tests/TestCase/Database/Expression/DistinctComparisonExpressionTest.php b/tests/TestCase/Database/Expression/DistinctComparisonExpressionTest.php
new file mode 100644
index 00000000000..b02338c76c3
--- /dev/null
+++ b/tests/TestCase/Database/Expression/DistinctComparisonExpressionTest.php
@@ -0,0 +1,63 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Database\Expression;
+
+use Cake\Database\Expression\DistinctComparisonExpression;
+use Cake\Database\Expression\IdentifierExpression;
+use Cake\Database\Expression\QueryExpression;
+use Cake\Database\ValueBinder;
+use Cake\TestSuite\TestCase;
+
+class DistinctComparisonExpressionTest extends TestCase
+{
+    public function testSqlWithIdentifierValue(): void
+    {
+        $expr = new DistinctComparisonExpression(
+            new IdentifierExpression('field'),
+            new IdentifierExpression('other_field'),
+            null,
+            'IS DISTINCT FROM',
+        );
+
+        $this->assertEqualsSql('field IS DISTINCT FROM other_field', $expr->sql(new ValueBinder()));
+    }
+
+    public function testSqlWithExpressionValue(): void
+    {
+        $expr = new DistinctComparisonExpression(
+            new IdentifierExpression('field'),
+            new QueryExpression(['other_field' => 'value']),
+            null,
+            'IS DISTINCT FROM',
+        );
+
+        $this->assertEqualsSql('field IS DISTINCT FROM (other_field = :c0)', $expr->sql(new ValueBinder()));
+    }
+
+    public function testSqlWithNotFlag(): void
+    {
+        $expr = new DistinctComparisonExpression(
+            new IdentifierExpression('field'),
+            'value',
+            null,
+            'IS DISTINCT FROM',
+        );
+        $expr->setNot(true);
+
+        $this->assertEqualsSql('NOT (field IS DISTINCT FROM :c0)', $expr->sql(new ValueBinder()));
+    }
+}
diff --git a/tests/TestCase/Database/Expression/QueryExpressionTest.php b/tests/TestCase/Database/Expression/QueryExpressionTest.php
index 3543645cef1..0ef58d6eeea 100644
--- a/tests/TestCase/Database/Expression/QueryExpressionTest.php
+++ b/tests/TestCase/Database/Expression/QueryExpressionTest.php
@@ -200,7 +200,7 @@ public static function methodsProvider(): array
     {
         return [
             ['eq'], ['notEq'], ['gt'], ['lt'], ['gte'], ['lte'], ['like'],
-            ['notLike'], ['in'], ['notIn'],
+            ['notLike'], ['in'], ['notIn'], ['inOrNull'], ['notInOrNull'], ['isDistinctFrom'], ['isNotDistinctFrom'],
         ];
     }
 
@@ -240,6 +240,19 @@ public function testEmptyOr(): void
         $this->assertCount(0, $expr);
     }
 
+    /**
+     * Tests that both conditions are generated for inOrNull().
+     */
+    public function testInOrNull(): void
+    {
+        $expr = new QueryExpression();
+        $expr->inOrNull('test', ['one', 'two']);
+        $this->assertEqualsSql(
+            '(test IN (:c0,:c1) OR (test) IS NULL)',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
     /**
      * Tests that both conditions are generated for notInOrNull().
      */
@@ -253,6 +266,108 @@ public function testNotInOrNull(): void
         );
     }
 
+    /**
+     * Tests that between() generates correct SQL.
+     */
+    public function testBetween(): void
+    {
+        $expr = new QueryExpression();
+        $expr->between('age', 18, 65);
+        $this->assertEqualsSql(
+            'age BETWEEN :c0 AND :c1',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests that notBetween() generates correct SQL.
+     */
+    public function testNotBetween(): void
+    {
+        $expr = new QueryExpression();
+        $expr->notBetween('age', 18, 65);
+        $this->assertEqualsSql(
+            'age NOT BETWEEN :c0 AND :c1',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests isDistinctFrom()
+     */
+    public function testIsDistinctFrom(): void
+    {
+        $expr = new QueryExpression();
+        $expr->isDistinctFrom('deleted_at', '2021-01-01');
+        $this->assertEqualsSql(
+            'deleted_at IS DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+
+        $expr = new QueryExpression();
+        $expr->isDistinctFrom('deleted_at', null);
+        $this->assertEqualsSql(
+            'deleted_at IS DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests isNotDistinctFrom()
+     */
+    public function testIsNotDistinctFrom(): void
+    {
+        $expr = new QueryExpression();
+        $expr->isNotDistinctFrom('deleted_at', '2021-01-01');
+        $this->assertEqualsSql(
+            'deleted_at IS NOT DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+
+        $expr = new QueryExpression();
+        $expr->isNotDistinctFrom('deleted_at', null);
+        $this->assertEqualsSql(
+            'deleted_at IS NOT DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests parsing IS DISTINCT FROM in array conditions
+     */
+    public function testParseIsDistinctFrom(): void
+    {
+        $expr = new QueryExpression(['deleted_at IS DISTINCT FROM' => '2021-01-01']);
+        $this->assertEqualsSql(
+            'deleted_at IS DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+
+        $expr = new QueryExpression(['deleted_at IS DISTINCT FROM' => null]);
+        $this->assertEqualsSql(
+            'deleted_at IS DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
+    /**
+     * Tests parsing IS NOT DISTINCT FROM in array conditions
+     */
+    public function testParseIsNotDistinctFrom(): void
+    {
+        $expr = new QueryExpression(['deleted_at IS NOT DISTINCT FROM' => '2021-01-01']);
+        $this->assertEqualsSql(
+            'deleted_at IS NOT DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+
+        $expr = new QueryExpression(['deleted_at IS NOT DISTINCT FROM' => null]);
+        $this->assertEqualsSql(
+            'deleted_at IS NOT DISTINCT FROM :c0',
+            $expr->sql(new ValueBinder()),
+        );
+    }
+
     public function testCaseWithoutValue(): void
     {
         $expression = (new QueryExpression())
diff --git a/tests/TestCase/Database/FunctionsBuilderTest.php b/tests/TestCase/Database/FunctionsBuilderTest.php
index 082c74f10ee..b6abe1c159b 100644
--- a/tests/TestCase/Database/FunctionsBuilderTest.php
+++ b/tests/TestCase/Database/FunctionsBuilderTest.php
@@ -18,6 +18,7 @@
 use Cake\Database\Expression\AggregateExpression;
 use Cake\Database\Expression\FunctionExpression;
 use Cake\Database\Expression\IdentifierExpression;
+use Cake\Database\Expression\StringAggExpression;
 use Cake\Database\FunctionsBuilder;
 use Cake\Database\ValueBinder;
 use Cake\TestSuite\TestCase;
@@ -134,6 +135,20 @@ public function testCount(): void
         $this->assertSame('integer', $function->getReturnType());
     }
 
+    /**
+     * Tests generating a portable STRING_AGG() function
+     */
+    public function testStringAgg(): void
+    {
+        $function = $this->functions->stringAgg('name', ',');
+        $this->assertInstanceOf(StringAggExpression::class, $function);
+        $this->assertSame('STRING_AGG(name, :param0)', $function->sql(new ValueBinder()));
+        $this->assertSame('string', $function->getReturnType());
+
+        $function = $this->functions->stringAgg('name', ',', ['sort_order' => 'DESC']);
+        $this->assertSame('STRING_AGG(name, :param0 ORDER BY sort_order DESC)', $function->sql(new ValueBinder()));
+    }
+
     /**
      * Tests generating a CONCAT() function
      */
diff --git a/tests/TestCase/Database/NullSafeComparisonTest.php b/tests/TestCase/Database/NullSafeComparisonTest.php
new file mode 100644
index 00000000000..2602f3f3d83
--- /dev/null
+++ b/tests/TestCase/Database/NullSafeComparisonTest.php
@@ -0,0 +1,77 @@
+<?php
+declare(strict_types=1);
+
+namespace Cake\Test\TestCase\Database;
+
+use Cake\Database\Connection;
+use Cake\Database\Driver\Mysql;
+use Cake\Database\Driver\Postgres;
+use Cake\Database\Driver\Sqlite;
+use Cake\Database\Driver\Sqlserver;
+use Cake\Database\Expression\QueryExpression;
+use Cake\Database\Query\SelectQuery;
+use Cake\Database\QueryCompiler;
+use Cake\Database\ValueBinder;
+use Cake\TestSuite\TestCase;
+use Mockery;
+use PHPUnit\Framework\Attributes\DataProvider;
+
+class NullSafeComparisonTest extends TestCase
+{
+    public static function dialectProvider(): array
+    {
+        return [
+            'PostgreSQL' => [Postgres::class, 'col IS DISTINCT FROM :c0', 'col IS NOT DISTINCT FROM :c0'],
+            'SQLite' => [Sqlite::class, 'col IS DISTINCT FROM :c0', 'col IS NOT DISTINCT FROM :c0'],
+            'SQLServer' => [Sqlserver::class, 'col IS DISTINCT FROM :c0', 'col IS NOT DISTINCT FROM :c0'],
+            'MySQL' => [Mysql::class, 'NOT (col <=> :c0)', 'col <=> :c0'],
+        ];
+    }
+
+    #[DataProvider('dialectProvider')]
+    public function testNullSafeComparisonSql(string $driverClass, string $expectedDistinct, string $expectedNotDistinct): void
+    {
+        $driver = Mockery::mock($driverClass)
+            ->makePartial()
+            ->shouldAllowMockingProtectedMethods();
+        $driver->shouldReceive('enabled')->andReturn(true);
+        $driver->shouldReceive('newCompiler')->andReturn(new QueryCompiler());
+        $driver->shouldReceive('version')->andReturn('8.0.0');
+        $driver->shouldReceive('getRole')->andReturn('write');
+        $driver->shouldReceive('supports')->andReturn(true);
+        $driver->shouldReceive('isAutoQuotingEnabled')->andReturn(false);
+
+        $connection = Mockery::mock(Connection::class);
+        $connection->shouldReceive('role')->andReturn('write');
+        $connection->shouldReceive('configName')->andReturn('test');
+        $connection->shouldReceive('getDriver')->andReturn($driver);
+        $connection->shouldReceive('selectQuery')->andReturnUsing(function () use ($connection) {
+            return new SelectQuery($connection);
+        });
+
+        $binder = new ValueBinder();
+
+        // IS DISTINCT FROM
+        $expr = new QueryExpression(['col IS DISTINCT FROM' => 'val']);
+        if ($driver instanceof Mysql) {
+            $query = $connection->selectQuery();
+            $query->where($expr);
+            $sql = $driver->compileQuery($query, $binder);
+            $this->assertStringContainsString($expectedDistinct, $sql);
+        } else {
+            $this->assertEqualsSql($expectedDistinct, $expr->sql($binder));
+        }
+
+        $binder = new ValueBinder();
+        // IS NOT DISTINCT FROM
+        $expr = new QueryExpression(['col IS NOT DISTINCT FROM' => 'val']);
+        if ($driver instanceof Mysql) {
+            $query = $connection->selectQuery();
+            $query->where($expr);
+            $sql = $driver->compileQuery($query, $binder);
+            $this->assertStringContainsString($expectedNotDistinct, $sql);
+        } else {
+            $this->assertEqualsSql($expectedNotDistinct, $expr->sql($binder));
+        }
+    }
+}
diff --git a/tests/TestCase/Database/Query/SelectQueryTest.php b/tests/TestCase/Database/Query/SelectQueryTest.php
index 7822e1f8254..a975f78b13a 100644
--- a/tests/TestCase/Database/Query/SelectQueryTest.php
+++ b/tests/TestCase/Database/Query/SelectQueryTest.php
@@ -2819,6 +2819,170 @@ public function testIntersectAll(): void
         $result->closeCursor();
     }
 
+    /**
+     * Tests that it is possible to one or multiple EXCEPT statements in a query
+     */
+    public function testExcept(): void
+    {
+        $this->skipIf(
+            !$this->connection->getDriver()->supports(DriverFeatureEnum::EXCEPT),
+            'Driver does not support EXCEPT clause.',
+        );
+
+        $except = (new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->where(['article_id' => 1]);
+        $query = new SelectQuery($this->connection);
+        $result = $query->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->except($except)
+            ->execute();
+        $rows = $result->fetchAll();
+        $expectedCount = count((new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->execute()
+            ->fetchAll()) -
+            count($except->execute()->fetchAll());
+
+        $this->assertCount($expectedCount, $rows);
+        $result->closeCursor();
+
+        $except = (new SelectQuery($this->connection))
+            ->select(['foo' => 'id', 'bar' => 'comment'])
+            ->from(['c' => 'comments'])
+            ->where(['article_id' => 2])
+            ->orderBy(['foo' => 'desc']);
+        $query = new SelectQuery($this->connection);
+        $expectedCount = count((new SelectQuery($this->connection))
+            ->select(['foo' => 'id', 'bar' => 'comment'])
+            ->from(['c' => 'comments'])
+            ->execute()
+            ->fetchAll()) - count($except->execute()->fetchAll());
+        $query->select(['foo' => 'id', 'bar' => 'comment'])
+            ->from(['c' => 'comments'])
+            ->except($except);
+        $result = $query->execute();
+        $rows2 = $result->fetchAll();
+
+        $this->assertCount($expectedCount, $rows2);
+        $this->assertNotEquals($rows, $rows2);
+        $result->closeCursor();
+
+        $except = (new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->where(['article_id' => 1])
+            ->from(['c' => 'comments']);
+        $query = new SelectQuery($this->connection);
+        $query->select(['id', 'comment'], true)
+            ->from(['c' => 'comments'])
+            ->except($except, true);
+        $result = $query->execute();
+        $rows3 = $result->fetchAll();
+
+        $this->assertCount(
+            count((new SelectQuery($this->connection))
+                ->select(['id', 'comment'])
+                ->from(['c' => 'comments'])
+                ->execute()
+                ->fetchAll()) - count($except->execute()->fetchAll()),
+            $rows3,
+        );
+        $this->assertEquals($rows, $rows3);
+        $result->closeCursor();
+    }
+
+    /**
+     * Tests that it is possible to run excepts with order by statements
+     */
+    public function testExceptOrderBy(): void
+    {
+        $this->skipIf(
+            !$this->connection->getDriver()->supports(DriverFeatureEnum::EXCEPT),
+            'Driver does not support EXCEPT clause.',
+        );
+        $this->skipIf(
+            !$this->connection->getDriver()->supports(DriverFeatureEnum::SET_OPERATIONS_ORDER_BY),
+            'Driver does not support ORDER BY on EXCEPTed queries.',
+        );
+        $except = (new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->where(['article_id' => 1])
+            ->orderBy(['c.id' => 'asc']);
+
+        $query = new SelectQuery($this->connection);
+        $result = $query->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->orderBy(['c.id' => 'asc'])
+            ->except($except)
+            ->execute();
+
+        $this->assertCount(
+            count((new SelectQuery($this->connection))
+                ->select(['id', 'comment'])
+                ->from(['c' => 'comments'])
+                ->execute()
+                ->fetchAll()) -
+                count($except->execute()->fetchAll()),
+            $result->fetchAll(),
+        );
+    }
+
+    /**
+     * Tests that EXCEPT ALL can be built
+     */
+    public function testExceptAll(): void
+    {
+        $this->skipIf(
+            !$this->connection->getDriver()->supports(DriverFeatureEnum::EXCEPT_ALL),
+            'Driver does not support EXCEPT ALL clause.',
+        );
+        $except = (new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->where(['article_id' => 1]);
+        $query = new SelectQuery($this->connection);
+        $result = $query->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->exceptAll($except)
+            ->execute();
+        $rows = $result->fetchAll('assoc');
+
+        $this->assertCount(
+            count((new SelectQuery($this->connection))
+                ->select(['id', 'comment'])
+                ->from(['c' => 'comments'])
+                ->execute()
+                ->fetchAll()) -
+                count($except->execute()->fetchAll()),
+            $rows,
+        );
+        $result->closeCursor();
+
+        $except = (new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->where(['article_id' => 2])
+            ->orderBy(['id' => 'desc']);
+        $query = new SelectQuery($this->connection);
+        $expectedCount = count((new SelectQuery($this->connection))
+            ->select(['id', 'comment'])
+            ->from(['c' => 'comments'])
+            ->execute()
+            ->fetchAll()) - count($except->execute()->fetchAll());
+        $query->select(['id', 'comment'], true)
+            ->from(['c' => 'comments'])
+            ->exceptAll($except, true);
+        $result = $query->execute();
+        $rows2 = $result->fetchAll();
+
+        $this->assertCount($expectedCount, $rows2);
+        $this->assertNotEquals($rows, $rows2);
+        $result->closeCursor();
+    }
+
     /**
      * Tests stacking decorators for results and resetting the list of decorators
      */
@@ -3486,7 +3650,7 @@ public function testDirectIsNull(): void
     public function testIsNullInvalid(): void
     {
         $this->expectException(InvalidArgumentException::class);
-        $this->expectExceptionMessage('Expression `name` has invalid `null` value. If `null` is a valid value, operator (IS, IS NOT) is missing.');
+        $this->expectExceptionMessage('Expression `name` has invalid `null` value. If `null` is a valid value, operator (IS, IS NOT, IS DISTINCT FROM, IS NOT DISTINCT FROM) is missing.');
 
         (new SelectQuery($this->connection))
             ->select(['name'])
diff --git a/tests/TestCase/Database/Schema/IndexTest.php b/tests/TestCase/Database/Schema/IndexTest.php
index 06997416dda..28f83e949f3 100644
--- a/tests/TestCase/Database/Schema/IndexTest.php
+++ b/tests/TestCase/Database/Schema/IndexTest.php
@@ -96,6 +96,35 @@ public function testSetWhere(): void
         $this->assertSame('status = 1 AND type = "active"', $index->getWhere());
     }
 
+    public function testSetAccessMethod(): void
+    {
+        $index = new Index('title_idx', ['title']);
+        $this->assertNull($index->getAccessMethod());
+
+        $index->setAccessMethod(Index::GIN);
+        $this->assertSame(Index::GIN, $index->getAccessMethod());
+
+        $index->setAccessMethod(Index::GIST);
+        $this->assertSame(Index::GIST, $index->getAccessMethod());
+
+        $index->setAccessMethod(null);
+        $this->assertNull($index->getAccessMethod());
+    }
+
+    public function testToArray(): void
+    {
+        $index = new Index('title_idx', ['title']);
+        $result = $index->toArray();
+
+        $this->assertSame('title_idx', $result['name']);
+        $this->assertSame(['title'], $result['columns']);
+        $this->assertArrayNotHasKey('accessMethod', $result);
+
+        $index->setAccessMethod(Index::GIN);
+        $result = $index->toArray();
+        $this->assertSame(Index::GIN, $result['accessMethod']);
+    }
+
     public function testSetAttributes(): void
     {
         $index = new Index('title_idx', ['title']);
diff --git a/tests/TestCase/Database/Schema/PostgresSchemaDialectTest.php b/tests/TestCase/Database/Schema/PostgresSchemaDialectTest.php
index fc6e7373d82..22191aa73a5 100644
--- a/tests/TestCase/Database/Schema/PostgresSchemaDialectTest.php
+++ b/tests/TestCase/Database/Schema/PostgresSchemaDialectTest.php
@@ -23,6 +23,7 @@
 use Cake\Database\Schema\CheckConstraint;
 use Cake\Database\Schema\Collection as SchemaCollection;
 use Cake\Database\Schema\ForeignKey;
+use Cake\Database\Schema\Index;
 use Cake\Database\Schema\PostgresSchemaDialect;
 use Cake\Database\Schema\TableSchema;
 use Cake\Database\Schema\UniqueKey;
@@ -721,7 +722,7 @@ public function testDescribeTableGeospatialTypes(): void
             $this->markTestSkipped('PostGIS extension is not available');
         }
 
-        // GEOMETRY defaults to srid 0 while GEOGRAPHY defaults to srid 4326
+        // Unconstrained columns default to srid 0, typed columns default to 4326 for geography
         $sql = <<<SQL
             CREATE TABLE ref_table (
                 geometry_geometry GEOMETRY,
@@ -749,7 +750,8 @@ public function testDescribeTableGeospatialTypes(): void
                 'length' => null,
                 'precision' => null,
                 'comment' => null,
-                'srid' => null,
+                'geometryType' => 'Geometry',
+                'srid' => 0,
             ],
             'geometry_point' => [
                 'type' => 'geometry',
@@ -758,7 +760,8 @@ public function testDescribeTableGeospatialTypes(): void
                 'length' => null,
                 'precision' => null,
                 'comment' => null,
-                'srid' => null,
+                'geometryType' => 'Point',
+                'srid' => 0,
             ],
             'geometry_point_4236' => [
                 'type' => 'geometry',
@@ -767,7 +770,8 @@ public function testDescribeTableGeospatialTypes(): void
                 'length' => null,
                 'precision' => null,
                 'comment' => null,
-                'srid' => null,
+                'geometryType' => 'Point',
+                'srid' => 4236,
             ],
             'geography_geometry' => [
                 'type' => 'geography',
@@ -776,6 +780,8 @@ public function testDescribeTableGeospatialTypes(): void
                 'length' => null,
                 'precision' => null,
                 'comment' => null,
+                'geometryType' => 'Geometry',
+                'srid' => 0,
             ],
             'geography_point' => [
                 'type' => 'geography',
@@ -784,6 +790,8 @@ public function testDescribeTableGeospatialTypes(): void
                 'length' => null,
                 'precision' => null,
                 'comment' => null,
+                'geometryType' => 'Point',
+                'srid' => 4326,
             ],
             'geography_point_0' => [
                 'type' => 'geography',
@@ -792,6 +800,8 @@ public function testDescribeTableGeospatialTypes(): void
                 'length' => null,
                 'precision' => null,
                 'comment' => null,
+                'geometryType' => 'Point',
+                'srid' => 4326,
             ],
         ];
 
@@ -1572,6 +1582,22 @@ public static function indexSqlProvider(): array
                 ['type' => 'index', 'columns' => ['author_id'], 'include' => ['title']],
                 'CREATE INDEX "author_idx" ON "schema_articles" ("author_id") INCLUDE ("title")',
             ],
+            // Access method tests
+            [
+                'title_gin_idx',
+                ['type' => 'index', 'columns' => ['title'], 'accessMethod' => 'gin'],
+                'CREATE INDEX "title_gin_idx" ON "schema_articles" USING gin ("title")',
+            ],
+            [
+                'title_gist_idx',
+                ['type' => 'index', 'columns' => ['title'], 'accessMethod' => 'gist'],
+                'CREATE INDEX "title_gist_idx" ON "schema_articles" USING gist ("title")',
+            ],
+            [
+                'title_hash_idx',
+                ['type' => 'index', 'columns' => ['title'], 'accessMethod' => 'hash'],
+                'CREATE INDEX "title_hash_idx" ON "schema_articles" USING hash ("title")',
+            ],
         ];
     }
 
@@ -1972,6 +1998,65 @@ public function testDescribeIndexIncludedFields(): void
         $this->assertEquals(['name'], $indexes[1]['include']);
     }
 
+    /**
+     * Test creating and describing indexes with non-btree access methods (GIN, GIST, HASH).
+     *
+     * This integration test verifies the full round-trip:
+     * 1. Generate SQL using indexSql() with accessMethod
+     * 2. Execute the SQL on the database
+     * 3. Describe the index and verify accessMethod is reflected
+     */
+    public function testIndexAccessMethodRoundTrip(): void
+    {
+        $this->_needsConnection();
+        $connection = ConnectionManager::get('test');
+        $connection->execute('DROP TABLE IF EXISTS schema_index_access_method');
+
+        // Create a table with JSONB column for GIN index testing
+        $sql = <<<SQL
+CREATE TABLE schema_index_access_method (
+    "id" INT NOT NULL GENERATED ALWAYS AS IDENTITY,
+    "data" JSONB,
+    "name" VARCHAR(255),
+    PRIMARY KEY("id")
+);
+SQL;
+        $connection->execute($sql);
+
+        // Create a TableSchema and add a GIN index
+        $table = (new TableSchema('schema_index_access_method'))
+            ->addColumn('id', ['type' => 'integer'])
+            ->addColumn('data', ['type' => 'json'])
+            ->addColumn('name', ['type' => 'string', 'length' => 255])
+            ->addIndex('data_gin_idx', [
+                'type' => 'index',
+                'columns' => ['data'],
+                'accessMethod' => Index::GIN,
+            ]);
+
+        // Generate and execute the index SQL
+        $dialect = new PostgresSchemaDialect($connection->getDriver());
+        $indexSql = $dialect->indexSql($table, 'data_gin_idx');
+        $connection->execute($indexSql);
+
+        // Describe the index and verify access method is reflected
+        $indexes = $dialect->describeIndexes('schema_index_access_method');
+        $connection->execute('DROP TABLE schema_index_access_method');
+
+        // Find the GIN index in results
+        $ginIndex = null;
+        foreach ($indexes as $index) {
+            if ($index['name'] === 'data_gin_idx') {
+                $ginIndex = $index;
+                break;
+            }
+        }
+
+        $this->assertNotNull($ginIndex, 'GIN index should be found');
+        $this->assertEquals(['data'], $ginIndex['columns']);
+        $this->assertEquals(Index::GIN, $ginIndex['accessMethod']);
+    }
+
     public function testDescribeForeignKeySql(): void
     {
         $driver = $this->createStub(Postgres::class);
diff --git a/tests/TestCase/Database/Type/DecimalTypeTest.php b/tests/TestCase/Database/Type/DecimalTypeTest.php
index 8d760044928..9e11cfaacac 100644
--- a/tests/TestCase/Database/Type/DecimalTypeTest.php
+++ b/tests/TestCase/Database/Type/DecimalTypeTest.php
@@ -227,6 +227,20 @@ public function testMarshalWithLocaleParsingDanish(): void
         $this->type->useLocaleParser(false);
     }
 
+    /**
+     * Tests marshalling invalid numbers returns null when using locale parser
+     */
+    public function testMarshalWithLocaleParsingInvalidReturnsNull(): void
+    {
+        $this->type->useLocaleParser();
+
+        I18n::setLocale('en_US');
+        $this->assertNull($this->type->marshal('invalid'));
+        $this->assertNull($this->type->marshal('abc'));
+
+        $this->type->useLocaleParser(false);
+    }
+
     /**
      * Test that exceptions are raised on invalid parsers.
      */
diff --git a/tests/TestCase/Database/Type/FloatTypeTest.php b/tests/TestCase/Database/Type/FloatTypeTest.php
index 805f65ba663..be577d9cf7a 100644
--- a/tests/TestCase/Database/Type/FloatTypeTest.php
+++ b/tests/TestCase/Database/Type/FloatTypeTest.php
@@ -175,6 +175,20 @@ public function testMarshalWithLocaleParsing(): void
         $this->type->useLocaleParser(false);
     }
 
+    /**
+     * Tests marshalling invalid numbers returns null when using locale parser
+     */
+    public function testMarshalWithLocaleParsingInvalidReturnsNull(): void
+    {
+        $this->type->useLocaleParser();
+
+        I18n::setLocale('en_US');
+        $this->assertNull($this->type->marshal('invalid'));
+        $this->assertNull($this->type->marshal('abc'));
+
+        $this->type->useLocaleParser(false);
+    }
+
     /**
      * Test that exceptions are raised on invalid parsers.
      */
diff --git a/tests/TestCase/Http/Link/LinkProviderTest.php b/tests/TestCase/Http/Link/LinkProviderTest.php
new file mode 100644
index 00000000000..6dc67219500
--- /dev/null
+++ b/tests/TestCase/Http/Link/LinkProviderTest.php
@@ -0,0 +1,161 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Http\Link;
+
+use Cake\Http\Link\Link;
+use Cake\Http\Link\LinkProvider;
+use Cake\TestSuite\TestCase;
+use Psr\Link\EvolvableLinkProviderInterface;
+use Psr\Link\LinkProviderInterface;
+
+/**
+ * LinkProviderTest class
+ */
+class LinkProviderTest extends TestCase
+{
+    /**
+     * Test that LinkProvider implements PSR-13 interfaces.
+     */
+    public function testImplementsInterfaces(): void
+    {
+        $provider = new LinkProvider();
+        $this->assertInstanceOf(LinkProviderInterface::class, $provider);
+        $this->assertInstanceOf(EvolvableLinkProviderInterface::class, $provider);
+    }
+
+    /**
+     * Test getLinks returns empty array by default.
+     */
+    public function testGetLinksEmpty(): void
+    {
+        $provider = new LinkProvider();
+        $this->assertSame([], iterator_to_array($provider->getLinks()));
+    }
+
+    /**
+     * Test getLinks with initial links.
+     */
+    public function testGetLinksWithInitial(): void
+    {
+        $link1 = new Link('/api/users', 'self');
+        $link2 = new Link('/api/users?page=2', 'next');
+
+        $provider = new LinkProvider([$link1, $link2]);
+        $links = iterator_to_array($provider->getLinks());
+
+        $this->assertCount(2, $links);
+        $this->assertSame($link1, $links[0]);
+        $this->assertSame($link2, $links[1]);
+    }
+
+    /**
+     * Test getLinksByRel.
+     */
+    public function testGetLinksByRel(): void
+    {
+        $link1 = new Link('/api/users', 'self');
+        $link2 = new Link('/api/users?page=2', 'next');
+        $link3 = new Link('/api', 'self');
+
+        $provider = new LinkProvider([$link1, $link2, $link3]);
+        $selfLinks = iterator_to_array($provider->getLinksByRel('self'));
+
+        $this->assertCount(2, $selfLinks);
+        $this->assertContains($link1, $selfLinks);
+        $this->assertContains($link3, $selfLinks);
+    }
+
+    /**
+     * Test getLinksByRel with no matches.
+     */
+    public function testGetLinksByRelNoMatches(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $provider = new LinkProvider([$link]);
+
+        $links = iterator_to_array($provider->getLinksByRel('next'));
+        $this->assertEmpty($links);
+    }
+
+    /**
+     * Test withLink adds link.
+     */
+    public function testWithLink(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $provider = new LinkProvider();
+
+        $new = $provider->withLink($link);
+
+        $this->assertNotSame($provider, $new);
+        $this->assertEmpty(iterator_to_array($provider->getLinks()));
+
+        $newLinks = iterator_to_array($new->getLinks());
+        $this->assertCount(1, $newLinks);
+        $this->assertSame($link, $newLinks[0]);
+    }
+
+    /**
+     * Test withLink does not duplicate same link instance.
+     */
+    public function testWithLinkNoDuplicates(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $provider = new LinkProvider([$link]);
+
+        $new = $provider->withLink($link);
+
+        $links = iterator_to_array($new->getLinks());
+        $this->assertCount(1, $links);
+    }
+
+    /**
+     * Test withoutLink removes link.
+     */
+    public function testWithoutLink(): void
+    {
+        $link1 = new Link('/api/users', 'self');
+        $link2 = new Link('/api/users?page=2', 'next');
+
+        $provider = new LinkProvider([$link1, $link2]);
+        $new = $provider->withoutLink($link1);
+
+        $this->assertNotSame($provider, $new);
+
+        $originalLinks = iterator_to_array($provider->getLinks());
+        $this->assertCount(2, $originalLinks);
+
+        $newLinks = iterator_to_array($new->getLinks());
+        $this->assertCount(1, $newLinks);
+        $this->assertSame($link2, $newLinks[0]);
+    }
+
+    /**
+     * Test withoutLink with non-existent link.
+     */
+    public function testWithoutLinkNotFound(): void
+    {
+        $link1 = new Link('/api/users', 'self');
+        $link2 = new Link('/api/users?page=2', 'next');
+
+        $provider = new LinkProvider([$link1]);
+        $new = $provider->withoutLink($link2);
+
+        $links = iterator_to_array($new->getLinks());
+        $this->assertCount(1, $links);
+    }
+}
diff --git a/tests/TestCase/Http/Link/LinkTest.php b/tests/TestCase/Http/Link/LinkTest.php
new file mode 100644
index 00000000000..c0609340b3f
--- /dev/null
+++ b/tests/TestCase/Http/Link/LinkTest.php
@@ -0,0 +1,179 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Http\Link;
+
+use Cake\Http\Link\Link;
+use Cake\TestSuite\TestCase;
+use Psr\Link\EvolvableLinkInterface;
+use Psr\Link\LinkInterface;
+
+/**
+ * LinkTest class
+ */
+class LinkTest extends TestCase
+{
+    /**
+     * Test that Link implements PSR-13 interfaces.
+     */
+    public function testImplementsInterfaces(): void
+    {
+        $link = new Link('/api/users');
+        $this->assertInstanceOf(LinkInterface::class, $link);
+        $this->assertInstanceOf(EvolvableLinkInterface::class, $link);
+    }
+
+    /**
+     * Test getHref.
+     */
+    public function testGetHref(): void
+    {
+        $link = new Link('/api/users');
+        $this->assertSame('/api/users', $link->getHref());
+    }
+
+    /**
+     * Test getRels with string.
+     */
+    public function testGetRelsString(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $this->assertSame(['self'], $link->getRels());
+    }
+
+    /**
+     * Test getRels with array.
+     */
+    public function testGetRelsArray(): void
+    {
+        $link = new Link('/api/users', ['self', 'collection']);
+        $this->assertSame(['self', 'collection'], $link->getRels());
+    }
+
+    /**
+     * Test getAttributes.
+     */
+    public function testGetAttributes(): void
+    {
+        $link = new Link('/api/users', 'self', ['type' => 'application/json']);
+        $this->assertSame(['type' => 'application/json'], $link->getAttributes());
+    }
+
+    /**
+     * Test isTemplated returns false for non-templated URI.
+     */
+    public function testIsTemplatedFalse(): void
+    {
+        $link = new Link('/api/users');
+        $this->assertFalse($link->isTemplated());
+    }
+
+    /**
+     * Test isTemplated returns true for templated URI.
+     */
+    public function testIsTemplatedTrue(): void
+    {
+        $link = new Link('/api/users/{id}');
+        $this->assertTrue($link->isTemplated());
+    }
+
+    /**
+     * Test withHref returns new instance.
+     */
+    public function testWithHref(): void
+    {
+        $link = new Link('/api/users');
+        $new = $link->withHref('/api/posts');
+
+        $this->assertNotSame($link, $new);
+        $this->assertSame('/api/users', $link->getHref());
+        $this->assertSame('/api/posts', $new->getHref());
+    }
+
+    /**
+     * Test withRel adds relation.
+     */
+    public function testWithRel(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $new = $link->withRel('collection');
+
+        $this->assertNotSame($link, $new);
+        $this->assertSame(['self'], $link->getRels());
+        $this->assertSame(['self', 'collection'], $new->getRels());
+    }
+
+    /**
+     * Test withRel does not duplicate relations.
+     */
+    public function testWithRelNoDuplicates(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $new = $link->withRel('self');
+
+        $this->assertSame(['self'], $new->getRels());
+    }
+
+    /**
+     * Test withoutRel removes relation.
+     */
+    public function testWithoutRel(): void
+    {
+        $link = new Link('/api/users', ['self', 'collection']);
+        $new = $link->withoutRel('self');
+
+        $this->assertNotSame($link, $new);
+        $this->assertSame(['self', 'collection'], $link->getRels());
+        $this->assertSame(['collection'], $new->getRels());
+    }
+
+    /**
+     * Test withAttribute adds attribute.
+     */
+    public function testWithAttribute(): void
+    {
+        $link = new Link('/api/users');
+        $new = $link->withAttribute('type', 'application/json');
+
+        $this->assertNotSame($link, $new);
+        $this->assertSame([], $link->getAttributes());
+        $this->assertSame(['type' => 'application/json'], $new->getAttributes());
+    }
+
+    /**
+     * Test withAttribute overwrites existing attribute.
+     */
+    public function testWithAttributeOverwrite(): void
+    {
+        $link = new Link('/api/users', [], ['type' => 'text/html']);
+        $new = $link->withAttribute('type', 'application/json');
+
+        $this->assertSame(['type' => 'application/json'], $new->getAttributes());
+    }
+
+    /**
+     * Test withoutAttribute removes attribute.
+     */
+    public function testWithoutAttribute(): void
+    {
+        $link = new Link('/api/users', [], ['type' => 'application/json', 'title' => 'Users']);
+        $new = $link->withoutAttribute('type');
+
+        $this->assertNotSame($link, $new);
+        $this->assertSame(['type' => 'application/json', 'title' => 'Users'], $link->getAttributes());
+        $this->assertSame(['title' => 'Users'], $new->getAttributes());
+    }
+}
diff --git a/tests/TestCase/Http/ResponseEmitterTest.php b/tests/TestCase/Http/ResponseEmitterTest.php
index ab00e265809..361d2800262 100644
--- a/tests/TestCase/Http/ResponseEmitterTest.php
+++ b/tests/TestCase/Http/ResponseEmitterTest.php
@@ -18,6 +18,7 @@
 
 use Cake\Http\CallbackStream;
 use Cake\Http\Cookie\Cookie;
+use Cake\Http\Link\Link;
 use Cake\Http\Response;
 use Cake\Http\ResponseEmitter;
 use Cake\TestSuite\TestCase;
@@ -366,4 +367,147 @@ public function testEmitResponseBodyRangeCallbackStream(): void
         ];
         $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
     }
+
+    /**
+     * Test emitting Link headers from PSR-13 links.
+     */
+    public function testEmitResponseLinks(): void
+    {
+        $response = (new Response())
+            ->withHeader('Content-Type', 'text/html')
+            ->withLink(new Link('/api/users', 'self'))
+            ->withLink(new Link('/api/users?page=2', 'next'));
+        $response->getBody()->write('ok');
+
+        ob_start();
+        $this->emitter->emit($response);
+        ob_get_clean();
+
+        $expected = [
+            'HTTP/1.1 200 OK',
+            'Content-Type: text/html',
+            'Link: </api/users>; rel="self"',
+            'Link: </api/users?page=2>; rel="next"',
+        ];
+        $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
+    }
+
+    /**
+     * Test emitting Link headers with attributes.
+     */
+    public function testEmitResponseLinksWithAttributes(): void
+    {
+        $link = (new Link('/css/app.css'))
+            ->withRel('preload')
+            ->withAttribute('as', 'style')
+            ->withAttribute('crossorigin', 'anonymous');
+        $response = (new Response())
+            ->withLink($link);
+        $response->getBody()->write('ok');
+
+        ob_start();
+        $this->emitter->emit($response);
+        ob_get_clean();
+
+        $expected = [
+            'HTTP/1.1 200 OK',
+            'Content-Type: text/html; charset=UTF-8',
+            'Link: </css/app.css>; rel="preload"; as="style"; crossorigin="anonymous"',
+        ];
+        $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
+    }
+
+    /**
+     * Test emitting Link headers with boolean attributes.
+     */
+    public function testEmitResponseLinksWithBooleanAttributes(): void
+    {
+        $link = (new Link('/script.js'))
+            ->withRel('preload')
+            ->withAttribute('as', 'script')
+            ->withAttribute('nopush', true)
+            ->withAttribute('disabled', false);
+        $response = (new Response())
+            ->withLink($link);
+        $response->getBody()->write('ok');
+
+        ob_start();
+        $this->emitter->emit($response);
+        ob_get_clean();
+
+        $expected = [
+            'HTTP/1.1 200 OK',
+            'Content-Type: text/html; charset=UTF-8',
+            'Link: </script.js>; rel="preload"; as="script"; nopush',
+        ];
+        $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
+    }
+
+    /**
+     * Test emitting Link headers with array attributes.
+     */
+    public function testEmitResponseLinksWithArrayAttributes(): void
+    {
+        $link = (new Link('/api/resource'))
+            ->withRel('self')
+            ->withAttribute('hreflang', ['en', 'de']);
+        $response = (new Response())
+            ->withLink($link);
+        $response->getBody()->write('ok');
+
+        ob_start();
+        $this->emitter->emit($response);
+        ob_get_clean();
+
+        $expected = [
+            'HTTP/1.1 200 OK',
+            'Content-Type: text/html; charset=UTF-8',
+            'Link: </api/resource>; rel="self"; hreflang="en"; hreflang="de"',
+        ];
+        $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
+    }
+
+    /**
+     * Test emitting Link headers escapes special characters.
+     */
+    public function testEmitResponseLinksEscapesValues(): void
+    {
+        $link = (new Link('/api/users'))
+            ->withRel('self')
+            ->withAttribute('title', 'A "quoted" value');
+        $response = (new Response())
+            ->withLink($link);
+        $response->getBody()->write('ok');
+
+        ob_start();
+        $this->emitter->emit($response);
+        ob_get_clean();
+
+        $expected = [
+            'HTTP/1.1 200 OK',
+            'Content-Type: text/html; charset=UTF-8',
+            'Link: </api/users>; rel="self"; title="A \"quoted\" value"',
+        ];
+        $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
+    }
+
+    /**
+     * Test no Link headers emitted when no links present.
+     */
+    public function testEmitResponseNoLinks(): void
+    {
+        $response = (new Response())
+            ->withHeader('Content-Type', 'text/html');
+        $response->getBody()->write('ok');
+
+        ob_start();
+        $this->emitter->emit($response);
+        ob_get_clean();
+
+        $expected = [
+            'HTTP/1.1 200 OK',
+            'Content-Type: text/html',
+        ];
+        $this->assertEquals($expected, $GLOBALS['mockedHeaders']);
+    }
 }
diff --git a/tests/TestCase/Http/ResponseTest.php b/tests/TestCase/Http/ResponseTest.php
index 2ff4f0a4c2c..a45cbac3a77 100644
--- a/tests/TestCase/Http/ResponseTest.php
+++ b/tests/TestCase/Http/ResponseTest.php
@@ -23,6 +23,8 @@
 use Cake\Http\Cookie\CookieCollection;
 use Cake\Http\CorsBuilder;
 use Cake\Http\Exception\NotFoundException;
+use Cake\Http\Link\Link;
+use Cake\Http\Link\LinkProvider;
 use Cake\Http\Response;
 use Cake\Http\ServerRequest;
 use Cake\I18n\DateTime;
@@ -1549,6 +1551,90 @@ public function testHasHeader(): void
         $this->assertFalse($response->hasHeader('accept'));
     }
 
+    /**
+     * Test withLink adds a link to the response.
+     */
+    public function testWithLink(): void
+    {
+        $response = new Response();
+        $link = new Link('/api/users', 'self');
+
+        $new = $response->withLink($link);
+
+        $this->assertNotSame($response, $new);
+        $this->assertCount(0, iterator_to_array($response->getLinks()->getLinks()));
+        $this->assertCount(1, iterator_to_array($new->getLinks()->getLinks()));
+
+        $links = iterator_to_array($new->getLinks()->getLinks());
+        $this->assertSame('/api/users', $links[0]->getHref());
+        $this->assertSame(['self'], $links[0]->getRels());
+    }
+
+    /**
+     * Test withLink can add multiple links.
+     */
+    public function testWithLinkMultiple(): void
+    {
+        $response = new Response();
+        $self = new Link('/api/users/1', 'self');
+        $next = new Link('/api/users?page=2', 'next');
+
+        $new = $response
+            ->withLink($self)
+            ->withLink($next);
+
+        $links = iterator_to_array($new->getLinks()->getLinks());
+        $this->assertCount(2, $links);
+        $this->assertSame('/api/users/1', $links[0]->getHref());
+        $this->assertSame('/api/users?page=2', $links[1]->getHref());
+    }
+
+    /**
+     * Test withoutLink removes a link from the response.
+     */
+    public function testWithoutLink(): void
+    {
+        $link = new Link('/api/users', 'self');
+        $response = (new Response())->withLink($link);
+
+        $new = $response->withoutLink($link);
+
+        $this->assertNotSame($response, $new);
+        $this->assertCount(1, iterator_to_array($response->getLinks()->getLinks()));
+        $this->assertCount(0, iterator_to_array($new->getLinks()->getLinks()));
+    }
+
+    /**
+     * Test getLinks returns the link provider.
+     */
+    public function testGetLinks(): void
+    {
+        $response = new Response();
+        $links = $response->getLinks();
+
+        $this->assertInstanceOf(LinkProvider::class, $links);
+        $this->assertCount(0, iterator_to_array($links->getLinks()));
+    }
+
+    /**
+     * Test withLinkProvider replaces the link provider.
+     */
+    public function testWithLinkProvider(): void
+    {
+        $response = new Response();
+        $provider = new LinkProvider([
+            new Link('/api/users', 'self'),
+            new Link('/api/users?page=2', 'next'),
+        ]);
+
+        $new = $response->withLinkProvider($provider);
+
+        $this->assertNotSame($response, $new);
+        $this->assertCount(0, iterator_to_array($response->getLinks()->getLinks()));
+        $this->assertSame($provider, $new->getLinks());
+        $this->assertCount(2, iterator_to_array($new->getLinks()->getLinks()));
+    }
+
     /**
      * Tests __debugInfo
      */
@@ -1567,6 +1653,7 @@ public function testDebugInfo(): void
             'file' => null,
             'fileRange' => [],
             'cookies' => new CookieCollection(),
+            'links' => new LinkProvider(),
             'cacheDirectives' => [],
             'body' => 'Foo',
         ];
diff --git a/tests/TestCase/I18n/NumberTest.php b/tests/TestCase/I18n/NumberTest.php
index c27c09665be..37f1b9a2c15 100644
--- a/tests/TestCase/I18n/NumberTest.php
+++ b/tests/TestCase/I18n/NumberTest.php
@@ -128,6 +128,17 @@ public function testParseFloat(): void
         $this->assertSame($expected, $result);
     }
 
+    /**
+     * testParseFloatReturnsNullOnFailure method
+     */
+    public function testParseFloatReturnsNullOnFailure(): void
+    {
+        I18n::setLocale('en_US');
+        $this->assertNull($this->Number->parseFloat('abc'));
+        $this->assertNull($this->Number->parseFloat('invalid'));
+        $this->assertNull($this->Number->parseFloat(''));
+    }
+
     /**
      * testFormatDelta method
      */
@@ -512,53 +523,117 @@ public function testToReadableSize(): void
         $expected = '45 Bytes';
         $this->assertSame($expected, $result);
 
+        $result = $this->Number->toReadableSize(1000);
+        $expected = '1 KB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024);
+        $expected = '1.02 KB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 + 123);
+        $expected = '1.15 KB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 512);
+        $expected = '524.29 KB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 - 1);
+        $expected = '1.05 MB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(512.05 * 1024 * 1024);
+        $expected = '536.92 MB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 * 1024 - 1);
+        $expected = '1.07 GB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 512);
+        $expected = '549.76 GB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 - 1);
+        $expected = '1.1 TB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 * 512);
+        $expected = '562.95 TB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 * 1024 - 1);
+        $expected = '1,125.9 TB';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 * 1024 * 1024);
+        $expected = '1,152,921.5 TB';
+        $this->assertSame($expected, $result);
+
+        $this->Number->setUseIecUnits(true);
+
+        $result = $this->Number->toReadableSize(0);
+        $expected = '0 Bytes';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(1);
+        $expected = '1 Byte';
+        $this->assertSame($expected, $result);
+
+        $result = $this->Number->toReadableSize(45);
+        $expected = '45 Bytes';
+        $this->assertSame($expected, $result);
+
         $result = $this->Number->toReadableSize(1023);
         $expected = '1,023 Bytes';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024);
-        $expected = '1 KB';
+        $expected = '1 KiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 + 123);
-        $expected = '1.12 KB';
+        $expected = '1.12 KiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 512);
-        $expected = '512 KB';
+        $expected = '512 KiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 - 1);
-        $expected = '1 MB';
+        $expected = '1 MiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(512.05 * 1024 * 1024);
-        $expected = '512.05 MB';
+        $expected = '512.05 MiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 * 1024 - 1);
-        $expected = '1 GB';
+        $expected = '1 GiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 512);
-        $expected = '512 GB';
+        $expected = '512 GiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 - 1);
-        $expected = '1 TB';
+        $expected = '1 TiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 * 512);
-        $expected = '512 TB';
+        $expected = '512 TiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 * 1024 - 1);
-        $expected = '1,024 TB';
+        $expected = '1,024 TiB';
         $this->assertSame($expected, $result);
 
         $result = $this->Number->toReadableSize(1024 * 1024 * 1024 * 1024 * 1024 * 1024);
-        $expected = '1,048,576 TB';
+        $expected = '1,048,576 TiB';
         $this->assertSame($expected, $result);
+
+        $this->Number->setUseIecUnits(false);
     }
 
     /**
@@ -568,10 +643,18 @@ public function testReadableSizeLocalized(): void
     {
         I18n::setLocale('fr_FR');
         $result = $this->Number->toReadableSize(1321205);
-        $this->assertSame('1,26 MB', $result);
+        $this->assertSame('1,32 MB', $result);
+
+        $result = $this->Number->toReadableSize(512.05 * 1024 * 1024 * 1024);
+        $this->assertSame('549,81 GB', $result);
+
+        $this->Number->setUseIecUnits(true);
+
+        $result = $this->Number->toReadableSize(1321205);
+        $this->assertSame('1,26 MiB', $result);
 
         $result = $this->Number->toReadableSize(512.05 * 1024 * 1024 * 1024);
-        $this->assertSame('512,05 GB', $result);
+        $this->assertSame('512,05 GiB', $result);
     }
 
     /**
diff --git a/tests/TestCase/ORM/Association/BelongsToManyTest.php b/tests/TestCase/ORM/Association/BelongsToManyTest.php
index 8db777d62df..26fc47d6086 100644
--- a/tests/TestCase/ORM/Association/BelongsToManyTest.php
+++ b/tests/TestCase/ORM/Association/BelongsToManyTest.php
@@ -193,13 +193,14 @@ public function testSorting(): void
     public function testRequiresKeys(): void
     {
         $assoc = new BelongsToMany('Test');
-        $this->assertTrue($assoc->requiresKeys());
-
-        $assoc->setStrategy(BelongsToMany::STRATEGY_SUBQUERY);
+        // Default strategy is now subquery, which doesn't require keys
         $this->assertFalse($assoc->requiresKeys());
 
         $assoc->setStrategy(BelongsToMany::STRATEGY_SELECT);
         $this->assertTrue($assoc->requiresKeys());
+
+        $assoc->setStrategy(BelongsToMany::STRATEGY_SUBQUERY);
+        $this->assertFalse($assoc->requiresKeys());
     }
 
     /**
diff --git a/tests/TestCase/ORM/Association/HasManyTest.php b/tests/TestCase/ORM/Association/HasManyTest.php
index 72fb5c89234..9922819c48c 100644
--- a/tests/TestCase/ORM/Association/HasManyTest.php
+++ b/tests/TestCase/ORM/Association/HasManyTest.php
@@ -26,6 +26,7 @@
 use Cake\Database\ExpressionInterface;
 use Cake\Database\TypeMap;
 use Cake\Datasource\ConnectionManager;
+use Cake\Datasource\EntityInterface;
 use Cake\Datasource\ResultSetInterface;
 use Cake\Log\Log;
 use Cake\ORM\Association;
@@ -233,13 +234,14 @@ public function testSorting(): void
     public function testRequiresKeys(): void
     {
         $assoc = new HasMany('Test');
-        $this->assertTrue($assoc->requiresKeys());
-
-        $assoc->setStrategy(HasMany::STRATEGY_SUBQUERY);
+        // Default strategy is now subquery, which doesn't require keys
         $this->assertFalse($assoc->requiresKeys());
 
         $assoc->setStrategy(HasMany::STRATEGY_SELECT);
         $this->assertTrue($assoc->requiresKeys());
+
+        $assoc->setStrategy(HasMany::STRATEGY_SUBQUERY);
+        $this->assertFalse($assoc->requiresKeys());
     }
 
     /**
@@ -334,7 +336,7 @@ public function testEagerLoaderWithOverrides(): void
             'sort' => ['id' => 'ASC'],
             'strategy' => 'select',
         ];
-        $this->article->hasMany('Comments');
+        $this->article->hasMany('Comments', ['strategy' => 'select']);
 
         $association = new HasMany('Articles', $config);
         $keys = [1, 2, 3, 4];
@@ -574,6 +576,8 @@ public function all(): ResultSetInterface
     public function testEagerloaderNoForeignKeys(): void
     {
         $authors = $this->getTableLocator()->get('Authors');
+        // Use select strategy explicitly to test that it throws when foreign key is missing
+        $authors->Articles->setStrategy(Association::STRATEGY_SELECT);
 
         $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage('Unable to load `Articles` association. Ensure foreign key in `Authors`');
@@ -828,6 +832,121 @@ public function testSubqueryWithLimitAndOrder(): void
         $this->assertCount(1, $result[1]->articles);
     }
 
+    /**
+     * Subquery strategy when a HAVING-referenced select alias would collide
+     * with the binding key column name. The collision must be avoided to
+     * prevent "Duplicate column name" errors in the generated subquery.
+     */
+    public function testSubqueryWithHavingAliasCollidingWithBindingKey(): void
+    {
+        $Authors = $this->getTableLocator()->get('Authors');
+        $Authors->Articles->setStrategy(Association::STRATEGY_SUBQUERY);
+
+        // Alias 'id' collides with the binding key column name. The collision
+        // guard must skip preserving the alias in the generated subquery to
+        // avoid producing a duplicate 'id' column.
+        $query = $Authors->find();
+        $result = $query
+            ->select([
+                'Authors.id',
+                'id' => $query->func()->concat(['x'], ['string']),
+                'cnt' => $query->func()->count($query->identifier('Authors.id')),
+            ])
+            ->contain('Articles')
+            ->groupBy(['Authors.id'])
+            ->having(['cnt >=' => 1], ['cnt' => 'integer'])
+            ->toArray();
+
+        $this->assertNotEmpty($result);
+    }
+
+    /**
+     * Subquery strategy when the same alias is referenced by both ORDER BY
+     * and HAVING. The HAVING branch must not re-add an alias already
+     * preserved by the ORDER BY branch.
+     */
+    public function testSubqueryWithHavingAndOrderOnSameAlias(): void
+    {
+        $this->skipIf(
+            ConnectionManager::get('test')->getDriver() instanceof Sqlserver,
+            'Sql Server does not provide a portable LENGTH() function',
+        );
+
+        $Authors = $this->getTableLocator()->get('Authors');
+        $Authors->Articles->setStrategy(Association::STRATEGY_SUBQUERY);
+
+        $query = $Authors->find();
+        $result = $query
+            ->select([
+                'name_length' => $query->func()->length(['Authors.name' => 'identifier']),
+            ])
+            ->enableAutoFields()
+            ->contain('Articles')
+            ->groupBy(['Authors.id'])
+            ->having(['name_length >' => 4], ['name_length' => 'integer'])
+            ->orderBy(['name_length' => 'DESC'])
+            ->toArray();
+
+        $this->assertNotEmpty($result);
+    }
+
+    /**
+     * Subquery strategy + HAVING on an aggregate alias.
+     * The aggregate must be preserved in SELECT but skipped in GROUP BY.
+     */
+    public function testSubqueryWithHavingOnAggregateAlias(): void
+    {
+        $Authors = $this->getTableLocator()->get('Authors');
+        $Authors->Articles->setStrategy(Association::STRATEGY_SUBQUERY);
+
+        $query = $Authors->find();
+        $result = $query
+            ->select([
+                'Authors.id',
+                'Authors.name',
+                'article_count' => $query->func()->count($query->identifier('Articles.id')),
+            ])
+            ->leftJoinWith('Articles')
+            ->contain('Articles')
+            ->groupBy(['Authors.id', 'Authors.name'])
+            ->having(['article_count >' => 0], ['article_count' => 'integer'])
+            ->toArray();
+
+        $this->assertNotEmpty($result);
+    }
+
+    /**
+     * Tests subquery strategy when the parent query uses HAVING on a SELECT alias.
+     *
+     * The alias must be preserved in the generated subquery SELECT, otherwise the
+     * HAVING clause references a column that no longer exists.
+     */
+    public function testSubqueryWithHavingOnSelectAlias(): void
+    {
+        $this->skipIf(
+            ConnectionManager::get('test')->getDriver() instanceof Sqlserver,
+            'Sql Server does not provide a portable LENGTH() function',
+        );
+
+        $Authors = $this->getTableLocator()->get('Authors');
+        $Authors->Articles->setStrategy(Association::STRATEGY_SUBQUERY);
+
+        $query = $Authors->find();
+        $result = $query
+            ->select([
+                'name_length' => $query->func()->length(['Authors.name' => 'identifier']),
+            ])
+            ->enableAutoFields()
+            ->contain('Articles')
+            ->groupBy(['Authors.id'])
+            ->having(['name_length >' => 5], ['name_length' => 'integer'])
+            ->toArray();
+
+        $names = array_map(fn(EntityInterface $author): string => $author->name, $result);
+        sort($names);
+        $this->assertSame(['garrett', 'mariano'], $names);
+    }
+
     /**
      * Assertion method for order by clause contents.
      *
diff --git a/tests/TestCase/ORM/TableTest.php b/tests/TestCase/ORM/TableTest.php
index 712067ea3a8..2ba18882da7 100644
--- a/tests/TestCase/ORM/TableTest.php
+++ b/tests/TestCase/ORM/TableTest.php
@@ -1875,7 +1875,10 @@ public function testReciprocalHasManyLoading(): void
         $table = new ArticlesTable([
             'connection' => $this->connection,
         ]);
-        $result = $table->find('all')->contain(['Authors' => ['Articles']])->first();
+        // Use select strategy explicitly for nested contain on PostgreSQL compatibility
+        $result = $table->find('all')
+            ->contain(['Authors' => ['Articles' => ['strategy' => 'select']]])
+            ->first();
         $this->assertCount(2, $result->author->articles);
         foreach ($result->author->articles as $article) {
             $this->assertInstanceOf(Article::class, $article);
@@ -2478,6 +2481,212 @@ public function testAfterSaveCommitWithTransactionRunning(): void
         $this->connection->commit();
     }
 
+    public function testAfterSaveCommitPreservesIsNewState(): void
+    {
+        $table = $this->getTableLocator()->get('users');
+        $data = new Entity([
+            'username' => 'isnewuser',
+            'created' => new DateTime('2013-10-10 00:00'),
+            'updated' => new DateTime('2013-10-10 00:00'),
+        ]);
+
+        $wasNew = null;
+        $table->getEventManager()->on('Model.afterSaveCommit', function ($e, $entity) use (&$wasNew): void {
+            $wasNew = $entity->isNew();
+        });
+
+        $this->connection->transactional(function () use ($table, $data): void {
+            $table->saveOrFail($data);
+        });
+
+        $this->assertTrue($wasNew, 'Entity should still report isNew() as true in afterSaveCommit for an INSERT');
+    }
+
+    public function testAfterSaveCommitFiringAfterOuterTransactionCommits(): void
+    {
+        $table = $this->getTableLocator()->get('users');
+        $data = new Entity([
+            'username' => 'superuser',
+            'created' => new DateTime('2013-10-10 00:00'),
+            'updated' => new DateTime('2013-10-10 00:00'),
+        ]);
+
+        $calledDuringTransaction = false;
+        $calledAfterCommit = false;
+        $listener = function ($e, $entity, $options) use (&$calledDuringTransaction, &$calledAfterCommit): void {
+            if ($this->connection->inTransaction()) {
+                $calledDuringTransaction = true;
+            } else {
+                $calledAfterCommit = true;
+            }
+        };
+        $table->getEventManager()->on('Model.afterSaveCommit', $listener);
+
+        $this->connection->transactional(function () use ($table, $data, &$calledDuringTransaction): void {
+            $table->saveOrFail($data);
+            // Event must NOT fire while transaction is still open
+            $this->assertFalse($calledDuringTransaction, 'afterSaveCommit must not fire during an open transaction');
+        });
+
+        // After transactional() returns, the outer transaction has committed.
+        // afterSaveCommit should have fired.
+        $this->assertFalse($calledDuringTransaction, 'afterSaveCommit must not fire during a transaction');
+        $this->assertTrue($calledAfterCommit, 'afterSaveCommit should fire after the outer transaction commits');
+    }
+
+    public function testAfterSaveCommitForCrossTableTransactional(): void
+    {
+        $usersTable = $this->getTableLocator()->get('users');
+        $articlesTable = $this->getTableLocator()->get('articles');
+
+        $userEventFired = false;
+        $articleEventFired = false;
+
+        $usersTable->getEventManager()->on('Model.afterSaveCommit', function () use (&$userEventFired): void {
+            $userEventFired = true;
+        });
+        $articlesTable->getEventManager()->on('Model.afterSaveCommit', function () use (&$articleEventFired): void {
+            $articleEventFired = true;
+        });
+
+        $this->connection->transactional(function () use ($usersTable, $articlesTable): void {
+            $user = new Entity([
+                'username' => 'crossuser',
+                'created' => new DateTime('2013-10-10 00:00'),
+                'updated' => new DateTime('2013-10-10 00:00'),
+            ]);
+            $usersTable->saveOrFail($user);
+
+            $article = new Entity([
+                'title' => 'Cross-table article',
+                'body' => 'Testing cross-table transactional saves',
+                'author_id' => $user->id,
+            ]);
+            $articlesTable->saveOrFail($article);
+        });
+
+        $this->assertTrue($userEventFired, 'afterSaveCommit should fire for users table after outer commit');
+        $this->assertTrue($articleEventFired, 'afterSaveCommit should fire for articles table after outer commit');
+    }
+
+    public function testAfterDeleteCommitFiringAfterOuterTransactionCommits(): void
+    {
+        $table = $this->getTableLocator()->get('users');
+
+        $called = false;
+        $listener = function ($e, $entity, $options) use (&$called): void {
+            $called = true;
+        };
+        $table->getEventManager()->on('Model.afterDeleteCommit', $listener);
+
+        $user = $table->get(1);
+
+        $this->connection->transactional(function () use ($table, $user): void {
+            $table->deleteOrFail($user);
+        });
+
+        $this->assertTrue($called, 'afterDeleteCommit should fire after the outer transaction commits');
+    }
+
+    public function testAfterSaveCommitNotFiredOnRollback(): void
+    {
+        $table = $this->getTableLocator()->get('users');
+        $data = new Entity([
+            'username' => 'rollbackuser',
+            'created' => new DateTime('2013-10-10 00:00'),
+            'updated' => new DateTime('2013-10-10 00:00'),
+        ]);
+
+        $called = false;
+        $listener = function ($e, $entity, $options) use (&$called): void {
+            $called = true;
+        };
+        $table->getEventManager()->on('Model.afterSaveCommit', $listener);
+
+        try {
+            $this->connection->transactional(function () use ($table, $data): void {
+                $table->saveOrFail($data);
+                throw new RuntimeException('Force rollback');
+            });
+        } catch (RuntimeException) {
+            // Expected
+        }
+
+        $this->assertFalse($called, 'afterSaveCommit should not fire when transaction is rolled back');
+    }
+
+    public function testSaveManyInsideTransactionalNoDoubleDispatch(): void
+    {
+        $table = $this->getTableLocator()->get('authors');
+        $entities = [
+            new Entity(['name' => 'Author A']),
+            new Entity(['name' => 'Author B']),
+        ];
+
+        $callCount = 0;
+        $table->getEventManager()->on('Model.afterSaveCommit', function () use (&$callCount): void {
+            $callCount++;
+        });
+
+        $this->connection->transactional(function () use ($table, $entities): void {
+            $table->saveManyOrFail($entities);
+        });
+
+        $this->assertSame(2, $callCount, 'afterSaveCommit should fire exactly once per entity');
+    }
+
+    public function testSaveManyStandaloneNoDoubleDispatch(): void
+    {
+        $table = $this->getTableLocator()->get('authors');
+        $entities = [
+            new Entity(['name' => 'Author C']),
+            new Entity(['name' => 'Author D']),
+        ];
+
+        $callCount = 0;
+        $table->getEventManager()->on('Model.afterSaveCommit', function () use (&$callCount): void {
+            $callCount++;
+        });
+
+        $table->saveManyOrFail($entities);
+
+        $this->assertSame(2, $callCount, 'afterSaveCommit should fire exactly once per entity');
+    }
+
+    public function testDeleteManyStandaloneFiresAfterDeleteCommit(): void
+    {
+        $table = $this->getTableLocator()->get('authors');
+        $entities = $table->find()->limit(2)->toArray();
+        $this->assertCount(2, $entities);
+
+        $callCount = 0;
+        $table->getEventManager()->on('Model.afterDeleteCommit', function () use (&$callCount): void {
+            $callCount++;
+        });
+
+        $table->deleteManyOrFail($entities);
+
+        $this->assertSame(2, $callCount, 'afterDeleteCommit should fire once per entity');
+    }
+
+    public function testDeleteManyInsideTransactionalFiresAfterDeleteCommit(): void
+    {
+        $table = $this->getTableLocator()->get('authors');
+        $entities = $table->find()->limit(2)->toArray();
+        $this->assertCount(2, $entities);
+
+        $callCount = 0;
+        $table->getEventManager()->on('Model.afterDeleteCommit', function () use (&$callCount): void {
+            $callCount++;
+        });
+
+        $this->connection->transactional(function () use ($table, $entities): void {
+            $table->deleteManyOrFail($entities);
+        });
+
+        $this->assertSame(2, $callCount, 'afterDeleteCommit should fire once per entity after outer commit');
+    }
+
     /**
      * Asserts the afterSaveCommit is not triggered if transaction is running.
      */
@@ -5888,6 +6097,31 @@ public function testFindOrCreateTransactions(): void
         $this->assertTrue($article->afterSaveCommit);
     }
 
+    /**
+     * Test that findOrCreate defers afterSaveCommit inside an outer transaction.
+     */
+    public function testFindOrCreateDefersAfterSaveCommitInOuterTransaction(): void
+    {
+        $articles = $this->getTableLocator()->get('Articles');
+        $calledAfterCommit = false;
+        $articles->getEventManager()->on('Model.afterSaveCommit', function () use (&$calledAfterCommit): void {
+            $calledAfterCommit = true;
+        });
+
+        $this->connection->begin();
+        $article = $articles->findOrCreate(
+            ['title' => 'Find Something New For Outer Txn'],
+            function ($article): void {
+                $article->title = 'Deferred Success';
+            },
+        );
+        $this->assertFalse($calledAfterCommit, 'afterSaveCommit must not fire while outer transaction is open');
+
+        $this->connection->commit();
+        $this->assertTrue($calledAfterCommit, 'afterSaveCommit should fire after outer transaction commits');
+        $this->assertSame('Deferred Success', $article->title);
+    }
+
     /**
      * Test that findOrCreate executes callable without transaction.
      */
diff --git a/tests/TestCase/TestSuite/TestCaseTest.php b/tests/TestCase/TestSuite/TestCaseTest.php
index 9d8dd3a153d..7899da65e4c 100644
--- a/tests/TestCase/TestSuite/TestCaseTest.php
+++ b/tests/TestCase/TestSuite/TestCaseTest.php
@@ -489,6 +489,119 @@ public function testGetMockForModelSetTable(): void
         ConnectionManager::dropAlias('custom_i18n_datasource');
     }
 
+    /**
+     * Make sure the mocked objects behaves as a table object as well as a mockery object
+     */
+    public function testMockModel(): void
+    {
+        static::setAppNamespace();
+        $entity = new Entity([]);
+
+        $Posts = $this->mockModel('Posts');
+
+        $this->assertInstanceOf(PostsTable::class, $Posts);
+        $this->assertSame('posts', $Posts->getTable());
+
+        $Posts = $this->mockModel('Posts');
+        $Posts->shouldReceive('save')
+            ->once()
+            ->andReturn(false);
+        $this->assertFalse($Posts->save($entity));
+        $this->assertSame(Entity::class, $Posts->getEntityClass());
+        $this->assertInstanceOf(Connection::class, $Posts->getConnection());
+        $this->assertSame('test', $Posts->getConnection()->configName());
+
+        $Tags = $this->mockModel('Tags');
+        $this->assertSame(Tag::class, $Tags->getEntityClass());
+    }
+
+    /**
+     * Test mockModel on secondary datasource.
+     */
+    public function testMockModelSecondaryDatasource(): void
+    {
+        ConnectionManager::alias('test', 'secondary');
+
+        $post = $this->mockModel(SecondaryPostsTable::class);
+        $this->assertSame('test', $post->getConnection()->configName());
+    }
+
+    /**
+     * test mockModel() with plugin models
+     */
+    public function testMockModelWithPlugin(): void
+    {
+        static::setAppNamespace();
+        $this->loadPlugins(['TestPlugin']);
+        $TestPluginComment = $this->mockModel('TestPlugin.TestPluginComments');
+
+        $result = $this->getTableLocator()->get('TestPlugin.TestPluginComments');
+        $this->assertInstanceOf(TestPluginCommentsTable::class, $result);
+        $this->assertSame($TestPluginComment, $result);
+
+        $TestPluginComment = $this->mockModel('TestPlugin.TestPluginComments');
+
+        $this->assertInstanceOf(TestPluginCommentsTable::class, $TestPluginComment);
+        $this->assertSame(Entity::class, $TestPluginComment->getEntityClass());
+        $TestPluginComment->shouldReceive('save')
+            ->once()
+            ->andReturn(false);
+
+        $entity = new Entity([]);
+        $this->assertFalse($TestPluginComment->save($entity));
+
+        $TestPluginAuthors = $this->mockModel('TestPlugin.Authors');
+        $this->assertInstanceOf(AuthorsTable::class, $TestPluginAuthors);
+        $this->assertSame(Author::class, $TestPluginAuthors->getEntityClass());
+        $this->clearPlugins();
+    }
+
+    /**
+     * Make sure the mock behaves correctly as a table object
+     */
+    public function testMockModelTable(): void
+    {
+        $Mock = $this->mockModel(
+            'Table',
+            ['alias' => 'Comments', 'className' => Table::class],
+        );
+
+        $result = $this->getTableLocator()->get('Comments');
+        $this->assertInstanceOf(Table::class, $result);
+        $this->assertSame('Comments', $Mock->getAlias());
+
+        $Mock->shouldReceive('save')
+            ->once()
+            ->andReturn(false);
+
+        $entity = new Entity([]);
+        $this->assertFalse($Mock->save($entity));
+
+        $allMethodsStubs = $this->mockModel(
+            'Table',
+            ['alias' => 'Comments', 'className' => Table::class],
+        );
+        $result = $this->getTableLocator()->get('Comments');
+        $this->assertInstanceOf(Table::class, $result);
+        $this->assertSame('Comments', $allMethodsStubs->getAlias());
+    }
+
+    /**
+     * Test getting a table mockery model that doesn't have a preset table name sets the proper name
+     */
+    public function testMockModelSetTable(): void
+    {
+        static::setAppNamespace();
+        ConnectionManager::alias('test', 'custom_i18n_datasource');
+
+        $I18n = $this->mockModel('CustomI18n');
+        $this->assertSame('custom_i18n_table', $I18n->getTable());
+
+        $Tags = $this->mockModel('Tags');
+        $this->assertSame('tags', $Tags->getTable());
+        ConnectionManager::dropAlias('custom_i18n_datasource');
+    }
+
     /**
      * Test loadRoutes() helper
      */
diff --git a/tests/TestCase/Utility/FilesystemTest.php b/tests/TestCase/Utility/FilesystemTest.php
index 6becea12457..83fbba836dc 100644
--- a/tests/TestCase/Utility/FilesystemTest.php
+++ b/tests/TestCase/Utility/FilesystemTest.php
@@ -108,4 +108,82 @@ public function testDeleteDirWithLinks(): void
         $this->assertTrue($this->fs->deleteDir($path));
         $this->assertFalse(file_exists($link));
     }
+
+    public function testFindRecursive(): void
+    {
+        $structure = [
+            'file1.php' => 'content',
+            'file2.txt' => 'content',
+            '.hidden' => [
+                'secret.php' => 'should not see this',
+            ],
+            'subdir' => [
+                'file3.php' => 'content',
+            ],
+        ];
+        vfsStream::create($structure);
+
+        $iterator = $this->fs->findRecursive($this->vfsPath);
+
+        $files = [];
+        foreach ($iterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertContains('file1.php', $files);
+        $this->assertContains('file2.txt', $files);
+        $this->assertContains('file3.php', $files);
+        // Hidden directories should be skipped
+        $this->assertNotContains('.hidden', $files);
+        $this->assertNotContains('secret.php', $files);
+    }
+
+    public function testFind(): void
+    {
+        $structure = [
+            'file1.php' => 'content',
+            'file2.txt' => 'content',
+            'subdir' => [
+                'file3.php' => 'should not see this (non-recursive)',
+            ],
+        ];
+        vfsStream::create($structure);
+
+        $iterator = $this->fs->find($this->vfsPath);
+
+        $files = [];
+        foreach ($iterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should only see top-level files, not subdirectories' contents
+        $this->assertContains('file1.php', $files);
+        $this->assertContains('file2.txt', $files);
+        $this->assertContains('subdir', $files);
+        $this->assertNotContains('file3.php', $files);
+    }
+
+    public function testFindWithCustomFilter(): void
+    {
+        $structure = [
+            'file1.php' => 'content',
+            'file2.txt' => 'content',
+            'file3.php' => 'content',
+            'subdir' => [],
+        ];
+        vfsStream::create($structure);
+
+        $filter = fn($file) => $file->isFile() && $file->getExtension() === 'php';
+        $iterator = $this->fs->find($this->vfsPath, $filter);
+
+        $files = [];
+        foreach ($iterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertContains('file1.php', $files);
+        $this->assertContains('file3.php', $files);
+        $this->assertNotContains('file2.txt', $files);
+        $this->assertNotContains('subdir', $files);
+    }
 }
diff --git a/tests/TestCase/Utility/Fs/FinderTest.php b/tests/TestCase/Utility/Fs/FinderTest.php
new file mode 100644
index 00000000000..7ef36cc8105
--- /dev/null
+++ b/tests/TestCase/Utility/Fs/FinderTest.php
@@ -0,0 +1,1394 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Utility\Fs;
+
+use Cake\TestSuite\TestCase;
+use Cake\Utility\Fs\Enum\DepthOperator;
+use Cake\Utility\Fs\Finder;
+use Iterator;
+use org\bovigo\vfs\vfsStream;
+use SplFileInfo;
+
+/**
+ * FinderTest class
+ */
+class FinderTest extends TestCase
+{
+    /**
+     * Test virtual filesystem
+     *
+     * @var \org\bovigo\vfs\vfsStreamDirectory
+     */
+    protected $root;
+
+    /**
+     * Setup test
+     *
+     * @return void
+     */
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        $this->root = vfsStream::setup('root', null, [
+            'src' => [
+                'Controller' => [
+                    'AppController.php' => '<?php',
+                    'UsersController.php' => '<?php',
+                ],
+                'Model' => [
+                    'Entity' => [
+                        'User.php' => '<?php',
+                    ],
+                    'Table' => [
+                        'UsersTable.php' => '<?php',
+                    ],
+                ],
+                'View' => [
+                    'layout.php' => '<?php',
+                ],
+            ],
+            'tests' => [
+                'TestCase' => [
+                    'Controller' => [
+                        'UsersControllerTest.php' => '<?php',
+                    ],
+                ],
+            ],
+            'webroot' => [
+                '.htaccess' => 'rules',
+                'index.php' => '<?php',
+                'css' => [
+                    'style.css' => 'body {}',
+                ],
+                'js' => [
+                    'app.js' => 'console.log();',
+                ],
+            ],
+        ]);
+    }
+
+    public function testBasicFind(): void
+    {
+        $finder = new Finder();
+        $files = $finder->in(vfsStream::url('root/src'))->files();
+
+        $this->assertInstanceOf(Iterator::class, $files);
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $this->assertCount(5, $paths);
+        $this->assertStringContainsString('AppController.php', implode(',', $paths));
+        $this->assertStringContainsString('UsersController.php', implode(',', $paths));
+        $this->assertStringContainsString('User.php', implode(',', $paths));
+    }
+
+    public function testMultiplePaths(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->in(vfsStream::url('root/tests'))
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        $this->assertEquals(6, $count);
+    }
+
+    public function testNamePattern(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*Controller.php')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        $this->assertCount(2, $paths);
+        $this->assertContains('AppController.php', $paths);
+        $this->assertContains('UsersController.php', $paths);
+    }
+
+    public function testExclude(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->exclude('tests')
+            ->exclude('webroot')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $this->assertStringNotContainsString('TestCase', implode(',', $paths));
+        $this->assertStringNotContainsString('webroot', implode(',', $paths));
+        $this->assertStringContainsString('src', implode(',', $paths));
+    }
+
+    public function testDepth(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(3, DepthOperator::LESS_THAN)
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        // Should find files at depth 0, 1, and 2
+        $this->assertEquals(5, $count);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(1)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Should find files in Controller/ and View/
+        $this->assertGreaterThan(0, count($paths));
+    }
+
+    public function testPath(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->path('Controller')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $this->assertStringContainsString('Controller', implode(',', $paths));
+        $this->assertStringNotContainsString('Model', implode(',', $paths));
+    }
+
+    public function testNotPath(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->notPath('Controller')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $this->assertStringNotContainsString('Controller', implode(',', $paths));
+        $this->assertStringContainsString('Model', implode(',', $paths));
+    }
+
+    public function testIgnoreHiddenFiles(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->ignoreHiddenFiles(false)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        $this->assertContains('.htaccess', $paths);
+    }
+
+    public function testIgnoreHiddenFilesByDefault(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Hidden files should be ignored by default
+        $this->assertNotContains('.htaccess', $paths);
+        $this->assertContains('index.php', $paths);
+        $this->assertContains('style.css', $paths);
+    }
+
+    public function testChaining(): void
+    {
+        $finder = new Finder();
+        $result = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*.php')
+            ->exclude('View')
+            ->depth(3, DepthOperator::LESS_THAN);
+
+        $this->assertInstanceOf(Finder::class, $result);
+    }
+
+    public function testGlobPatternSimpleWildcard(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->name('*.css')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        $this->assertContains('style.css', $paths);
+        $this->assertCount(1, $paths);
+    }
+
+    public function testGlobPatternRecursiveWildcard(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*.php')
+            ->files();
+
+        // Should find all PHP files recursively (name filters filename only)
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        $this->assertEquals(5, $count);
+    }
+
+    public function testGlobPatternWithPath(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('User*.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('User.php', $filenames);
+        $this->assertContains('UsersTable.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertCount(3, $filenames);
+    }
+
+    public function testGlobPatternMultipleExtensions(): void
+    {
+        $finder = new Finder();
+
+        // Test .js files
+        $jsFiles = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->name('*.js')
+            ->files();
+
+        $count = 0;
+        foreach ($jsFiles as $file) {
+            $this->assertEquals('js', $file->getExtension());
+            $count++;
+        }
+        $this->assertEquals(1, $count);
+
+        // Test .css files
+        $finder2 = new Finder();
+        $cssFiles = $finder2
+            ->in(vfsStream::url('root/webroot'))
+            ->name('*.css')
+            ->files();
+
+        $count = 0;
+        foreach ($cssFiles as $file) {
+            $this->assertEquals('css', $file->getExtension());
+            $count++;
+        }
+        $this->assertEquals(1, $count);
+    }
+
+    public function testGlobPatternWithExclude(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*.php')
+            ->exclude('Controller')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $pathString = implode(',', $paths);
+        $this->assertStringNotContainsString('Controller', $pathString);
+        $this->assertStringContainsString('Model', $pathString);
+    }
+
+    public function testGlobPatternSpecificDirectory(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->path('Controller')
+            ->name('*Controller.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('AppController.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertCount(2, $filenames);
+    }
+
+    public function testPatternMethod(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('src/**/*.php')
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        // Should find all PHP files under src/
+        $this->assertEquals(5, $count);
+    }
+
+    public function testPatternMethodControllers(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('src/Controller/*.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('AppController.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertCount(2, $filenames);
+    }
+
+    public function testPatternMethodMultiple(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('src/**/*Controller.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('AppController.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertCount(2, $filenames);
+    }
+
+    public function testPatternMethodCssFiles(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('webroot/**/*.css')
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $this->assertEquals('css', $file->getExtension());
+            $count++;
+        }
+
+        $this->assertEquals(1, $count);
+    }
+
+    public function testPatternWithExclude(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('src/**/*.php')
+            ->exclude('Controller')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $pathString = implode(',', $paths);
+        $this->assertStringNotContainsString('Controller', $pathString);
+        $this->assertStringContainsString('Model', $pathString);
+    }
+
+    public function testPatternWithDepth(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->pattern('**/*.php')
+            ->depth(1)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        // Should find files at depth 1 (src/Controller/, src/View/)
+        $this->assertContains('AppController.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertContains('layout.php', $filenames);
+    }
+
+    public function testMultiplePatterns(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('**/*.css')
+            ->pattern('**/*.js')
+            ->files();
+
+        $extensions = [];
+        foreach ($files as $file) {
+            $extensions[] = $file->getExtension();
+        }
+
+        $this->assertContains('css', $extensions);
+        $this->assertContains('js', $extensions);
+        $this->assertCount(2, $extensions);
+    }
+
+    public function testComplexFiltering(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*.php')
+            ->path('Model')
+            ->notPath('Entity')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $pathString = implode(',', $paths);
+        $this->assertStringContainsString('Model', $pathString);
+        $this->assertStringContainsString('Table', $pathString);
+        $this->assertStringNotContainsString('Entity', $pathString);
+    }
+
+    public function testMultipleInPaths(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src/Controller'))
+            ->in(vfsStream::url('root/src/View'))
+            ->name('*.php')
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        // 2 controllers + 1 view file
+        $this->assertEquals(3, $count);
+    }
+
+    public function testPatternWithMultipleInPaths(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->in(vfsStream::url('root/tests'))
+            ->pattern('**/*Controller*.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('AppController.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertContains('UsersControllerTest.php', $filenames);
+    }
+
+    public function testNoMatches(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->pattern('**/*.nonexistent')
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        $this->assertEquals(0, $count);
+    }
+
+    public function testNameAndPathCombination(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->name('User*.php')
+            ->path('Table')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('UsersTable.php', $filenames);
+        $this->assertNotContains('UsersController.php', $filenames);
+        $this->assertCount(1, $filenames);
+    }
+
+    public function testDepthZero(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->depth(0)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('index.php', $filenames);
+        $this->assertNotContains('style.css', $filenames); // In subdirectory
+    }
+
+    public function testExcludeMultiple(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->name('*.php')
+            ->exclude('tests')
+            ->exclude('webroot')
+            ->exclude('View')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        $pathString = implode(',', $paths);
+        $this->assertStringNotContainsString('tests', $pathString);
+        $this->assertStringNotContainsString('webroot', $pathString);
+        $this->assertStringNotContainsString('View', $pathString);
+        $this->assertStringContainsString('Controller', $pathString);
+    }
+
+    public function testNotName(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*.php')
+            ->notName('*Controller.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('User.php', $filenames);
+        $this->assertContains('UsersTable.php', $filenames);
+        $this->assertContains('layout.php', $filenames);
+        $this->assertNotContains('AppController.php', $filenames);
+        $this->assertNotContains('UsersController.php', $filenames);
+    }
+
+    public function testNotNameMultiple(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->name('*.*')
+            ->notName('*.php')
+            ->notName('.htaccess')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertContains('style.css', $filenames);
+        $this->assertContains('app.js', $filenames);
+        $this->assertNotContains('index.php', $filenames);
+        $this->assertNotContains('.htaccess', $filenames);
+    }
+
+    public function testNameWithNotName(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('User*.php')
+            ->notName('*Table.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        // Should match User*.php (User.php, UsersController.php) but exclude *Table.php (UsersTable.php)
+        $this->assertContains('User.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertNotContains('UsersTable.php', $filenames);
+        $this->assertCount(2, $filenames);
+    }
+
+    public function testRecursiveFalse(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->recursive(false)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        // Should only find files at top level of src/
+        // src/ directory itself has no files, only subdirectories
+        $this->assertCount(0, $filenames);
+    }
+
+    public function testNonRecursiveWithFiles(): void
+    {
+        // Create structure with files at top level
+        vfsStream::setup('test', null, [
+            'top.php' => '<?php',
+            'another.php' => '<?php',
+            'subdir' => [
+                'deep.php' => '<?php',
+            ],
+        ]);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('test'))
+            ->recursive(false)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertCount(2, $filenames);
+        $this->assertContains('top.php', $filenames);
+        $this->assertContains('another.php', $filenames);
+        $this->assertNotContains('deep.php', $filenames);
+    }
+
+    public function testNonRecursiveWithNameFilter(): void
+    {
+        vfsStream::setup('test', null, [
+            'match.php' => '<?php',
+            'ignore.txt' => 'text',
+            'another.php' => '<?php',
+        ]);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('test'))
+            ->recursive(false)
+            ->name('*.php')
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertCount(2, $filenames);
+        $this->assertContains('match.php', $filenames);
+        $this->assertContains('another.php', $filenames);
+        $this->assertNotContains('ignore.txt', $filenames);
+    }
+
+    public function testNonRecursiveIgnoresHiddenFiles(): void
+    {
+        vfsStream::setup('test', null, [
+            'visible.txt' => 'content',
+            '.hidden' => 'hidden content',
+        ]);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('test'))
+            ->recursive(false)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertCount(1, $filenames);
+        $this->assertContains('visible.txt', $filenames);
+        $this->assertNotContains('.hidden', $filenames);
+    }
+
+    public function testNonRecursiveMultipleDirectories(): void
+    {
+        vfsStream::setup('test', null, [
+            'dir1' => [
+                'a.txt' => 'content',
+            ],
+            'dir2' => [
+                'b.txt' => 'content',
+            ],
+        ]);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('test/dir1'))
+            ->in(vfsStream::url('test/dir2'))
+            ->recursive(false)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertCount(2, $filenames);
+        $this->assertContains('a.txt', $filenames);
+        $this->assertContains('b.txt', $filenames);
+    }
+
+    public function testExcludeNestedDirectory(): void
+    {
+        // Create structure with nested directories to verify early pruning
+        $structure = [
+            'project' => [
+                'src' => [
+                    'file1.php' => '<?php',
+                    'vendor' => [
+                        'package1' => [
+                            'file2.php' => '<?php',
+                            'src' => [
+                                'deep.php' => '<?php',
+                            ],
+                        ],
+                        'package2' => [
+                            'file3.php' => '<?php',
+                        ],
+                    ],
+                ],
+            ],
+        ];
+
+        vfsStream::setup('exclude_test', null, $structure);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('exclude_test/project'))
+            ->exclude('vendor')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        // Should only find file1.php, not anything in vendor/
+        $this->assertCount(1, $paths);
+        $this->assertStringContainsString('file1.php', $paths[0]);
+        $this->assertStringNotContainsString('vendor', implode(',', $paths));
+        $this->assertStringNotContainsString('file2.php', implode(',', $paths));
+        $this->assertStringNotContainsString('file3.php', implode(',', $paths));
+        $this->assertStringNotContainsString('deep.php', implode(',', $paths));
+    }
+
+    public function testDirectories(): void
+    {
+        $finder = new Finder();
+        $directories = $finder->in(vfsStream::url('root/src'))->directories();
+
+        $this->assertInstanceOf(Iterator::class, $directories);
+
+        $paths = [];
+        foreach ($directories as $dir) {
+            $paths[] = $dir->getFilename();
+        }
+
+        // Should find: Controller, Model, View, Entity, Table (all directories)
+        $this->assertContains('Controller', $paths);
+        $this->assertContains('Model', $paths);
+        $this->assertContains('View', $paths);
+        $this->assertContains('Entity', $paths);
+        $this->assertContains('Table', $paths);
+
+        // Should not contain any files
+        $this->assertNotContains('AppController.php', $paths);
+        $this->assertNotContains('User.php', $paths);
+    }
+
+    public function testDirectoriesNonRecursive(): void
+    {
+        $finder = new Finder();
+        $directories = $finder
+            ->in(vfsStream::url('root/src'))
+            ->recursive(false)
+            ->directories();
+
+        $paths = [];
+        foreach ($directories as $dir) {
+            $paths[] = $dir->getFilename();
+        }
+
+        // Should only find top-level directories: Controller, Model, View
+        $this->assertCount(3, $paths);
+        $this->assertContains('Controller', $paths);
+        $this->assertContains('Model', $paths);
+        $this->assertContains('View', $paths);
+
+        // Should not find nested directories
+        $this->assertNotContains('Entity', $paths);
+        $this->assertNotContains('Table', $paths);
+    }
+
+    public function testDirectoriesWithExclude(): void
+    {
+        $finder = new Finder();
+        $directories = $finder
+            ->in(vfsStream::url('root/src'))
+            ->exclude('Model')
+            ->directories();
+
+        $paths = [];
+        foreach ($directories as $dir) {
+            $paths[] = $dir->getFilename();
+        }
+
+        $this->assertContains('Controller', $paths);
+        $this->assertContains('View', $paths);
+
+        // Model and its subdirectories should be excluded
+        $this->assertNotContains('Model', $paths);
+        $this->assertNotContains('Entity', $paths);
+        $this->assertNotContains('Table', $paths);
+    }
+
+    public function testDirectoriesWithDepth(): void
+    {
+        $finder = new Finder();
+        $directories = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(0)
+            ->directories();
+
+        $paths = [];
+        foreach ($directories as $dir) {
+            $paths[] = $dir->getFilename();
+        }
+
+        // Only top-level directories
+        $this->assertCount(3, $paths);
+        $this->assertContains('Controller', $paths);
+        $this->assertContains('Model', $paths);
+        $this->assertContains('View', $paths);
+    }
+
+    public function testDirectoriesWithNamePattern(): void
+    {
+        $finder = new Finder();
+        $directories = $finder
+            ->in(vfsStream::url('root/tests'))
+            ->name('*Case')
+            ->recursive(false)
+            ->directories();
+
+        $paths = [];
+        foreach ($directories as $dir) {
+            $paths[] = $dir->getFilename();
+        }
+
+        // Should match TestCase directory under tests/
+        $this->assertCount(1, $paths);
+        $this->assertContains('TestCase', $paths);
+    }
+
+    public function testAllMode(): void
+    {
+        $finder = new Finder();
+        $items = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(0)
+            ->all();
+
+        $files = [];
+        $directories = [];
+        foreach ($items as $item) {
+            if ($item->isDir()) {
+                $directories[] = $item->getFilename();
+            } else {
+                $files[] = $item->getFilename();
+            }
+        }
+
+        // Should find both files and directories at depth 0
+        $this->assertGreaterThan(0, $files);
+        $this->assertGreaterThan(0, $directories);
+        $this->assertContains('Controller', $directories);
+        $this->assertContains('Model', $directories);
+        $this->assertContains('View', $directories);
+    }
+
+    public function testAllModeRecursive(): void
+    {
+        $finder = new Finder();
+        $items = $finder
+            ->in(vfsStream::url('root/src/Model'))
+            ->all();
+
+        $files = [];
+        $directories = [];
+        foreach ($items as $item) {
+            if ($item->isDir()) {
+                $directories[] = $item->getFilename();
+            } else {
+                $files[] = $item->getFilename();
+            }
+        }
+
+        // Should find both Entity and Table directories
+        $this->assertContains('Entity', $directories);
+        $this->assertContains('Table', $directories);
+        // And their files
+        $this->assertContains('User.php', $files);
+        $this->assertContains('UsersTable.php', $files);
+    }
+
+    public function testRegexPathPattern(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->path('/Controller/')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        // Should match files with 'Controller' in path using regex
+        $this->assertGreaterThan(0, $paths);
+        $this->assertStringContainsString('Controller', implode(',', $paths));
+        $this->assertStringContainsString('UsersController.php', implode(',', $paths));
+    }
+
+    public function testRegexPathPatternWithDelimiters(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->path('#Model/(Entity|Table)#')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        // Should match files in Model/Entity or Model/Table
+        $this->assertCount(2, $paths);
+        $this->assertStringContainsString('User.php', implode(',', $paths));
+        $this->assertStringContainsString('UsersTable.php', implode(',', $paths));
+    }
+
+    public function testMultipleNamePatterns(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->name('*.css')
+            ->name('*.js')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Should match both CSS and JS files
+        $this->assertCount(2, $paths);
+        $this->assertContains('style.css', $paths);
+        $this->assertContains('app.js', $paths);
+    }
+
+    public function testDepthNotEqual(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(0, DepthOperator::NOT_EQUAL)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        // Should exclude depth 0 files, only get nested files
+        $this->assertGreaterThan(0, $paths);
+        // All paths should have at least one subdirectory
+        foreach ($paths as $path) {
+            $relativePath = str_replace(vfsStream::url('root/src') . '/', '', $path);
+            $this->assertStringContainsString('/', $relativePath);
+        }
+    }
+
+    public function testDepthGreaterThan(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(0, DepthOperator::GREATER_THAN)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        // Should only get files deeper than depth 0
+        $this->assertGreaterThan(0, $paths);
+        foreach ($paths as $path) {
+            $relativePath = str_replace(vfsStream::url('root/src') . '/', '', $path);
+            $this->assertStringContainsString('/', $relativePath);
+        }
+    }
+
+    public function testDepthLessThanOrEqual(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(1, DepthOperator::LESS_THAN_OR_EQUAL)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Should get files at depth 0 and 1
+        $this->assertGreaterThan(0, $paths);
+        // Should include layout.php (depth 1: src/View/layout.php)
+        $this->assertContains('layout.php', $paths);
+        // Should NOT include User.php (depth 2: src/Model/Entity/User.php)
+        $this->assertNotContains('User.php', $paths);
+    }
+
+    public function testDepthGreaterThanOrEqual(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(1, DepthOperator::GREATER_THAN_OR_EQUAL)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Should get files at depth 1 and deeper
+        $this->assertGreaterThan(0, $paths);
+        // Should include both depth 1 and depth 2 files
+        $this->assertContains('layout.php', $paths); // depth 1
+        $this->assertContains('User.php', $paths); // depth 2
+    }
+
+    public function testDepthRangeQuery(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->depth(0, DepthOperator::GREATER_THAN) // Greater than 0
+            ->depth(2, DepthOperator::LESS_THAN) // Less than 2
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Should only get files at depth 1 (between 0 and 2)
+        $this->assertGreaterThan(0, $paths);
+        $this->assertContains('layout.php', $paths); // depth 1
+        $this->assertContains('AppController.php', $paths); // depth 1
+        $this->assertNotContains('User.php', $paths); // depth 2
+    }
+
+    public function testIgnoreHiddenFilesFalse(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/webroot'))
+            ->ignoreHiddenFiles(false)
+            ->recursive(false)
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getFilename();
+        }
+
+        // Should include .htaccess file
+        $this->assertContains('.htaccess', $paths);
+        $this->assertContains('index.php', $paths);
+    }
+
+    public function testEmptyDirectory(): void
+    {
+        // Create an empty directory
+        vfsStream::create(['empty' => []], $this->root);
+
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/empty'))
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        // Should return no files
+        $this->assertSame(0, $count);
+    }
+
+    public function testConflictingNameFilters(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*Controller.php')
+            ->notName('*Controller.php')
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        // Should return no files due to conflicting filters
+        $this->assertSame(0, $count);
+    }
+
+    public function testMultiplePathPatternsOr(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->path('Controller')
+            ->path('Entity')
+            ->files();
+
+        $paths = [];
+        foreach ($files as $file) {
+            $paths[] = $file->getPathname();
+        }
+
+        // Should match files with either Controller OR Entity in path
+        $this->assertGreaterThan(0, $paths);
+        $this->assertStringContainsString('Controller', implode(',', $paths));
+        $this->assertStringContainsString('Entity', implode(',', $paths));
+        $this->assertStringContainsString('User.php', implode(',', $paths));
+        $this->assertStringContainsString('UsersController.php', implode(',', $paths));
+    }
+
+    /**
+     * Test filter() with single callback
+     */
+    public function testFilterSingleCallback(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->filter(function (SplFileInfo $file) {
+                // Only files with "Controller" in name
+                return str_contains($file->getFilename(), 'Controller');
+            })
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        $this->assertCount(2, $filenames);
+        $this->assertContains('AppController.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+    }
+
+    /**
+     * Test filter() with multiple chained callbacks (AND logic)
+     */
+    public function testFilterMultipleCallbacks(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->filter(fn(SplFileInfo $file) => str_contains($file->getFilename(), 'User'))
+            ->filter(fn(SplFileInfo $file) => !str_contains($file->getFilename(), 'Table'))
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        // Should find User.php and UsersController.php, but not UsersTable.php
+        $this->assertCount(2, $filenames);
+        $this->assertContains('User.php', $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertNotContains('UsersTable.php', $filenames);
+    }
+
+    /**
+     * Test filter() with relative path parameter
+     */
+    public function testFilterWithRelativePath(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root'))
+            ->filter(function (SplFileInfo $file, string $relativePath) {
+                // Only files in src directory
+                return str_starts_with($relativePath, 'src');
+            })
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+            $this->assertStringContainsString('src', $file->getPathname());
+        }
+
+        $this->assertGreaterThan(0, $count);
+    }
+
+    /**
+     * Test filter() combined with other filters
+     */
+    public function testFilterWithOtherFilters(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->name('*Controller.php')
+            ->filter(fn(SplFileInfo $file) => strlen($file->getFilename()) > 18)
+            ->files();
+
+        $filenames = [];
+        foreach ($files as $file) {
+            $filenames[] = $file->getFilename();
+        }
+
+        // UsersController.php (20 chars) is >18, AppController.php (17 chars) is not
+        $this->assertCount(1, $filenames);
+        $this->assertContains('UsersController.php', $filenames);
+        $this->assertNotContains('AppController.php', $filenames);
+    }
+
+    /**
+     * Test filter() returning empty results
+     */
+    public function testFilterNoMatches(): void
+    {
+        $finder = new Finder();
+        $files = $finder
+            ->in(vfsStream::url('root/src'))
+            ->filter(fn(SplFileInfo $file) => str_contains($file->getFilename(), 'NonExistent'))
+            ->files();
+
+        $count = 0;
+        foreach ($files as $file) {
+            $count++;
+        }
+
+        $this->assertSame(0, $count);
+    }
+}
diff --git a/tests/TestCase/Utility/Fs/Iterator/FilterIteratorTest.php b/tests/TestCase/Utility/Fs/Iterator/FilterIteratorTest.php
new file mode 100644
index 00000000000..d680bcf9ee7
--- /dev/null
+++ b/tests/TestCase/Utility/Fs/Iterator/FilterIteratorTest.php
@@ -0,0 +1,241 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Utility\Fs\Iterator;
+
+use Cake\TestSuite\TestCase;
+use Cake\Utility\Fs\Enum\FinderMode;
+use Cake\Utility\Fs\Iterator\CallbackFilterIterator;
+use Cake\Utility\Fs\Iterator\ExcludeDirectoryFilterIterator;
+use Cake\Utility\Fs\Iterator\FileTypeFilterIterator;
+use Cake\Utility\Fs\Iterator\HiddenFileFilterIterator;
+use FilesystemIterator;
+use org\bovigo\vfs\vfsStream;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
+use SplFileInfo;
+
+/**
+ * FilterIteratorTest class
+ */
+class FilterIteratorTest extends TestCase
+{
+    /**
+     * Test virtual filesystem
+     *
+     * @var \org\bovigo\vfs\vfsStreamDirectory
+     */
+    protected $root;
+
+    /**
+     * Setup test
+     *
+     * @return void
+     */
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        $this->root = vfsStream::setup('root', null, [
+            'visible.txt' => 'content',
+            '.hidden' => 'hidden content',
+            'file.php' => '<?php',
+            'src' => [
+                'Controller.php' => '<?php',
+                '.git' => [
+                    'config' => 'git config',
+                ],
+                'vendor' => [
+                    'package.php' => '<?php',
+                ],
+                'tests' => [
+                    'Test.php' => '<?php',
+                ],
+            ],
+        ]);
+    }
+
+    public function testHiddenFileFilterIterator(): void
+    {
+        $directory = new RecursiveDirectoryIterator(
+            vfsStream::url('root'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        $filtered = new HiddenFileFilterIterator($directory);
+        $iterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($iterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertContains('visible.txt', $files);
+        $this->assertContains('file.php', $files);
+        $this->assertNotContains('.hidden', $files);
+        $this->assertNotContains('.git', $files);
+    }
+
+    public function testFileTypeFilterIteratorFiles(): void
+    {
+        $directory = new FilesystemIterator(
+            vfsStream::url('root/src'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        $filtered = new FileTypeFilterIterator($directory, FinderMode::FILES);
+
+        $items = [];
+        foreach ($filtered as $file) {
+            $items[] = $file->getFilename();
+        }
+
+        $this->assertContains('Controller.php', $items);
+        $this->assertNotContains('vendor', $items);
+        $this->assertNotContains('tests', $items);
+    }
+
+    public function testFileTypeFilterIteratorDirectories(): void
+    {
+        $directory = new FilesystemIterator(
+            vfsStream::url('root/src'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        $filtered = new FileTypeFilterIterator($directory, FinderMode::DIRECTORIES);
+
+        $items = [];
+        foreach ($filtered as $file) {
+            $items[] = $file->getFilename();
+        }
+
+        $this->assertContains('vendor', $items);
+        $this->assertContains('tests', $items);
+        $this->assertContains('.git', $items);
+        $this->assertNotContains('Controller.php', $items);
+    }
+
+    public function testFileTypeFilterIteratorAll(): void
+    {
+        $directory = new FilesystemIterator(
+            vfsStream::url('root/src'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        $filtered = new FileTypeFilterIterator($directory, FinderMode::ALL);
+
+        $items = [];
+        foreach ($filtered as $file) {
+            $items[] = $file->getFilename();
+        }
+
+        $this->assertContains('Controller.php', $items);
+        $this->assertContains('vendor', $items);
+        $this->assertContains('tests', $items);
+    }
+
+    public function testExcludeDirectoryFilterIterator(): void
+    {
+        $directory = new RecursiveDirectoryIterator(
+            vfsStream::url('root/src'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        $filtered = new ExcludeDirectoryFilterIterator($directory, ['vendor', 'tests']);
+        $iterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($iterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertContains('Controller.php', $files);
+        $this->assertNotContains('package.php', $files); // in vendor
+        $this->assertNotContains('Test.php', $files); // in tests
+    }
+
+    public function testExcludeDirectoryFilterIteratorFilesPass(): void
+    {
+        $directory = new RecursiveDirectoryIterator(
+            vfsStream::url('root/src'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        // Even if filename matches excluded name, files should pass
+        $filtered = new ExcludeDirectoryFilterIterator($directory, ['Controller.php']);
+        $iterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($iterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // File with same name should still be included
+        $this->assertContains('Controller.php', $files);
+    }
+
+    public function testCombineFilters(): void
+    {
+        $directory = new RecursiveDirectoryIterator(
+            vfsStream::url('root'),
+            FilesystemIterator::SKIP_DOTS,
+        );
+
+        // Combine hidden file filter and exclude directory filter
+        $filtered = new HiddenFileFilterIterator($directory);
+        $filtered = new ExcludeDirectoryFilterIterator($filtered, ['vendor']);
+        $iterator = new RecursiveIteratorIterator($filtered);
+        $filtered = new FileTypeFilterIterator($iterator, FinderMode::FILES);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertContains('visible.txt', $files);
+        $this->assertContains('file.php', $files);
+        $this->assertContains('Controller.php', $files);
+        $this->assertNotContains('.hidden', $files); // hidden
+        $this->assertNotContains('config', $files); // in .git (hidden)
+        $this->assertNotContains('package.php', $files); // in vendor (excluded)
+    }
+
+    /**
+     * Test CallbackFilterIterator basic filtering
+     */
+    public function testCallbackFilterIterator(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new CallbackFilterIterator(
+            $recursiveIterator,
+            fn(SplFileInfo $file) => str_ends_with($file->getFilename(), '.php'),
+            $this->root->url(),
+        );
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertContains('file.php', $files);
+        $this->assertContains('Controller.php', $files);
+        $this->assertNotContains('visible.txt', $files);
+    }
+}
diff --git a/tests/TestCase/Utility/Fs/Iterator/PatternFilterIteratorTest.php b/tests/TestCase/Utility/Fs/Iterator/PatternFilterIteratorTest.php
new file mode 100644
index 00000000000..224a0beb91b
--- /dev/null
+++ b/tests/TestCase/Utility/Fs/Iterator/PatternFilterIteratorTest.php
@@ -0,0 +1,519 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Utility\Fs\Iterator;
+
+use Cake\TestSuite\TestCase;
+use Cake\Utility\Fs\Enum\DepthOperator;
+use Cake\Utility\Fs\Iterator\ContainsPathFilterIterator;
+use Cake\Utility\Fs\Iterator\DepthFilterIterator;
+use Cake\Utility\Fs\Iterator\FilenameFilterIterator;
+use Cake\Utility\Fs\Iterator\GlobFilterIterator;
+use org\bovigo\vfs\vfsStream;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
+
+/**
+ * Tests for pattern-based filter iterators
+ */
+class PatternFilterIteratorTest extends TestCase
+{
+    /**
+     * @var \org\bovigo\vfs\vfsStreamDirectory
+     */
+    protected $root;
+
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        $structure = [
+            'src' => [
+                'Controller' => [
+                    'AppController.php' => '<?php',
+                    'UsersController.php' => '<?php',
+                ],
+                'Model' => [
+                    'User.php' => '<?php',
+                    'Post.php' => '<?php',
+                ],
+                'View' => [
+                    'index.ctp' => '<h1>Hello</h1>',
+                    'layout.ctp' => '<html></html>',
+                ],
+            ],
+            'tests' => [
+                'TestCase' => [
+                    'UserTest.php' => '<?php',
+                    'PostTest.php' => '<?php',
+                ],
+            ],
+            'README.md' => '# Project',
+            'composer.json' => '{}',
+        ];
+
+        $this->root = vfsStream::setup('root', null, $structure);
+    }
+
+    /**
+     * Test FilenameFilterIterator with simple pattern
+     */
+    public function testFilenameFilterSimplePattern(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new FilenameFilterIterator($recursiveIterator, ['*.php']);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertCount(6, $files);
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UserTest.php', $files);
+        $this->assertNotContains('index.ctp', $files);
+        $this->assertNotContains('README.md', $files);
+    }
+
+    /**
+     * Test FilenameFilterIterator with multiple patterns
+     */
+    public function testFilenameFilterMultiplePatterns(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new FilenameFilterIterator($recursiveIterator, ['*.md', '*.json']);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertCount(2, $files);
+        $this->assertContains('README.md', $files);
+        $this->assertContains('composer.json', $files);
+    }
+
+    /**
+     * Test ContainsPathFilterIterator with regex patterns
+     */
+    public function testContainsPathFilterRegex(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $filtered = new ContainsPathFilterIterator($iterator, [
+            '/Controller\.php$/',
+            '/Test\.php$/',
+        ]);
+        $recursiveIterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($recursiveIterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertCount(4, $files);
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UsersController.php', $files);
+        $this->assertContains('UserTest.php', $files);
+        $this->assertContains('PostTest.php', $files);
+        $this->assertNotContains('User.php', $files);
+        $this->assertNotContains('Post.php', $files);
+    }
+
+    /**
+     * Test DepthFilterIterator with EQUAL operator
+     */
+    public function testDepthFilterEqual(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new DepthFilterIterator($recursiveIterator, DepthOperator::EQUAL, 0);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Only root level items (2 files)
+        $this->assertCount(2, $files);
+        $this->assertContains('README.md', $files);
+        $this->assertContains('composer.json', $files);
+    }
+
+    /**
+     * Test DepthFilterIterator with GREATER_THAN operator
+     */
+    public function testDepthFilterGreaterThan(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new DepthFilterIterator($recursiveIterator, DepthOperator::GREATER_THAN, 1);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // Files at depth > 1 (inside Controller, Model, View, TestCase directories)
+        $this->assertCount(8, $files);
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UserTest.php', $files);
+    }
+
+    /**
+     * Test DepthFilterIterator with LESS_THAN_OR_EQUAL operator
+     */
+    public function testDepthFilterLessThanOrEqual(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new DepthFilterIterator($recursiveIterator, DepthOperator::LESS_THAN_OR_EQUAL, 0);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // Only files at depth 0
+        $this->assertCount(2, $files);
+        $this->assertContains('README.md', $files);
+        $this->assertContains('composer.json', $files);
+    }
+
+    /**
+     * Test DepthFilterIterator with NOT_EQUAL operator
+     */
+    public function testDepthFilterNotEqual(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new DepthFilterIterator($recursiveIterator, DepthOperator::NOT_EQUAL, 0);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // All files except depth 0 (excludes README.md and composer.json, only 8 files at depth 2)
+        $this->assertCount(8, $files);
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UserTest.php', $files);
+        $this->assertNotContains('README.md', $files);
+        $this->assertNotContains('composer.json', $files);
+    }
+
+    /**
+     * Test DepthFilterIterator with LESS_THAN operator
+     */
+    public function testDepthFilterLessThan(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new DepthFilterIterator($recursiveIterator, DepthOperator::LESS_THAN, 1);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // Only files at depth < 1 (depth 0)
+        $this->assertCount(2, $files);
+        $this->assertContains('README.md', $files);
+        $this->assertContains('composer.json', $files);
+    }
+
+    /**
+     * Test DepthFilterIterator with GREATER_THAN_OR_EQUAL operator
+     */
+    public function testDepthFilterGreaterThanOrEqual(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new DepthFilterIterator($recursiveIterator, DepthOperator::GREATER_THAN_OR_EQUAL, 2);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // Files at depth >= 2 (inside Controller, Model, View, TestCase directories)
+        $this->assertCount(8, $files);
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UsersController.php', $files);
+        $this->assertContains('User.php', $files);
+        $this->assertContains('Post.php', $files);
+    }
+
+    /**
+     * Test FilenameFilterIterator with negate parameter (single pattern)
+     */
+    public function testFilenameFilterNegatedSinglePattern(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new FilenameFilterIterator($recursiveIterator, ['*Test.php'], negate: true);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should exclude UserTest.php and PostTest.php
+        $this->assertNotContains('UserTest.php', $files);
+        $this->assertNotContains('PostTest.php', $files);
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('User.php', $files);
+    }
+
+    /**
+     * Test FilenameFilterIterator with negate parameter (multiple patterns)
+     */
+    public function testFilenameFilterNegatedMultiplePatterns(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new FilenameFilterIterator($recursiveIterator, ['*.md', '*.json'], negate: true);
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        $this->assertNotContains('README.md', $files);
+        $this->assertNotContains('composer.json', $files);
+        $this->assertContains('AppController.php', $files);
+    }
+
+    /**
+     * Test ContainsPathFilterIterator with negate parameter (single pattern)
+     */
+    public function testContainsPathFilterNegatedSinglePattern(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $filtered = new ContainsPathFilterIterator($iterator, ['Controller'], negate: true);
+
+        $recursiveIterator = new RecursiveIteratorIterator($filtered);
+        $files = [];
+        foreach ($recursiveIterator as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // Should exclude files with 'Controller' in path
+        $this->assertNotContains('AppController.php', $files);
+        $this->assertNotContains('UsersController.php', $files);
+        $this->assertContains('User.php', $files);
+        $this->assertContains('UserTest.php', $files);
+    }
+
+    /**
+     * Test ContainsPathFilterIterator with negate allows directory traversal
+     */
+    public function testContainsPathFilterNegatedAllowsDirectoryTraversal(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $filtered = new ContainsPathFilterIterator($iterator, ['Controller'], negate: true);
+
+        $recursiveIterator = new RecursiveIteratorIterator($filtered);
+        $files = [];
+        foreach ($recursiveIterator as $file) {
+            if ($file->isFile()) {
+                $files[] = $file->getFilename();
+            }
+        }
+
+        // Should still find files in other directories even though traversing through src
+        $this->assertGreaterThan(0, $files);
+        $this->assertContains('User.php', $files);
+    }
+
+    /**
+     * Test ContainsPathFilterIterator with single pattern
+     */
+    public function testContainsPathFilterSinglePattern(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $filtered = new ContainsPathFilterIterator($iterator, ['Model']);
+        $recursiveIterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($recursiveIterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should only include files with 'Model' in path
+        $this->assertCount(2, $files);
+        $this->assertContains('User.php', $files);
+        $this->assertContains('Post.php', $files);
+    }
+
+    /**
+     * Test ContainsPathFilterIterator with multiple patterns (OR logic)
+     */
+    public function testContainsPathFilterMultiplePatterns(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $filtered = new ContainsPathFilterIterator($iterator, ['Controller', 'TestCase']);
+        $recursiveIterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($recursiveIterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should include files with either 'Controller' or 'TestCase' in path
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UsersController.php', $files);
+        $this->assertContains('UserTest.php', $files);
+        $this->assertContains('PostTest.php', $files);
+        $this->assertNotContains('User.php', $files); // In Model, not Controller/TestCase
+    }
+
+    /**
+     * Test ContainsPathFilterIterator with mixed string and regex patterns
+     */
+    public function testContainsPathFilterMixedPatterns(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        // Mix string pattern 'TestCase' with regex pattern matching Controller files
+        $filtered = new ContainsPathFilterIterator($iterator, ['TestCase', '/Controller\.php$/']);
+        $recursiveIterator = new RecursiveIteratorIterator($filtered);
+
+        $files = [];
+        foreach ($recursiveIterator as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should include files matching either pattern
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('UsersController.php', $files);
+        $this->assertContains('UserTest.php', $files);
+        $this->assertContains('PostTest.php', $files);
+        $this->assertNotContains('User.php', $files);
+        $this->assertNotContains('Post.php', $files);
+    }
+
+    /**
+     * Test GlobFilterIterator with simple pattern
+     */
+    public function testGlobFilterSimplePattern(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new GlobFilterIterator($recursiveIterator, ['src/**/*.php'], $this->root->url());
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should match all PHP files under src/
+        $this->assertContains('AppController.php', $files);
+        $this->assertContains('User.php', $files);
+        $this->assertNotContains('UserTest.php', $files); // In tests/, not src/
+    }
+
+    /**
+     * Test GlobFilterIterator with multiple patterns
+     */
+    public function testGlobFilterMultiplePatterns(): void
+    {
+        $iterator = new RecursiveDirectoryIterator(
+            $this->root->url(),
+            RecursiveDirectoryIterator::SKIP_DOTS,
+        );
+        $recursiveIterator = new RecursiveIteratorIterator($iterator);
+        $filtered = new GlobFilterIterator(
+            $recursiveIterator,
+            ['**/*Test.php', '*.md'],
+            $this->root->url(),
+        );
+
+        $files = [];
+        foreach ($filtered as $file) {
+            $files[] = $file->getFilename();
+        }
+
+        // Should match test files and markdown files
+        $this->assertContains('UserTest.php', $files);
+        $this->assertContains('PostTest.php', $files);
+        $this->assertContains('README.md', $files);
+        $this->assertNotContains('User.php', $files);
+    }
+}
diff --git a/tests/TestCase/Utility/Fs/PathTest.php b/tests/TestCase/Utility/Fs/PathTest.php
new file mode 100644
index 00000000000..e44eb4a1735
--- /dev/null
+++ b/tests/TestCase/Utility/Fs/PathTest.php
@@ -0,0 +1,77 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP(tm) Project
+ * @since         5.4.0
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Utility\Fs;
+
+use Cake\TestSuite\TestCase;
+use Cake\Utility\Fs\Path;
+
+/**
+ * Path test case
+ */
+class PathTest extends TestCase
+{
+    public function testNormalize(): void
+    {
+        $this->assertSame('path/to/file', Path::normalize('path\to\file'));
+        $this->assertSame('path/to/file', Path::normalize('path/to/file'));
+        $this->assertSame('C:/Windows/System', Path::normalize('C:\Windows\System'));
+    }
+
+    public function testNormalizeWithTrailing(): void
+    {
+        $this->assertSame('path/to/dir', Path::normalize('path/to/dir/'));
+        $this->assertSame('path/to/dir/', Path::normalize('path/to/dir/', trailing: true));
+        $this->assertSame('path/to/dir/', Path::normalize('path/to/dir', trailing: true));
+        $this->assertSame('/', Path::normalize('/', trailing: true));
+        $this->assertSame('', Path::normalize('/'));
+    }
+
+    public function testMakeRelative(): void
+    {
+        $this->assertSame('src/Model/Table.php', Path::makeRelative('/var/www/src/Model/Table.php', '/var/www'));
+        $this->assertSame('src/file.php', Path::makeRelative('/var/www/src/file.php', '/var/www/'));
+        $this->assertSame('', Path::makeRelative('/var/www', '/var/www'));
+
+        // Cross-platform
+        $this->assertSame('src/file.php', Path::makeRelative('C:\project\src\file.php', 'C:\project'));
+
+        // Going up directories
+        $this->assertSame('../other/path', Path::makeRelative('/var/other/path', '/var/www'));
+    }
+
+    public function testJoin(): void
+    {
+        $this->assertSame('path/to/file', Path::join('path', 'to', 'file'));
+        $this->assertSame('/absolute/path/file', Path::join('/absolute', 'path', 'file'));
+        $this->assertSame('path/to/file', Path::join('path/', '/to/', '/file'));
+        $this->assertSame('path/to/file', Path::join('path\\', '\\to\\', '\\file'));
+        $this->assertSame('', Path::join());
+        $this->assertSame('path', Path::join('path'));
+        $this->assertSame('path/file', Path::join('path', '', 'file'));
+    }
+
+    public function testMatches(): void
+    {
+        $this->assertTrue(Path::matches('*.php', 'file.php'));
+        $this->assertFalse(Path::matches('*.php', 'file.txt'));
+        $this->assertTrue(Path::matches('src/**/*.php', 'src/Model/Table.php'));
+        $this->assertTrue(Path::matches('vendor/**', 'vendor/lib/file.php'));
+        $this->assertFalse(Path::matches('tests/**', 'src/file.php'));
+        $this->assertTrue(Path::matches('src/*/Table.php', 'src/Model/Table.php'));
+        $this->assertTrue(Path::matches('**/file.php', 'deep/nested/path/file.php'));
+    }
+}
diff --git a/tests/TestCase/Utility/SecurityTest.php b/tests/TestCase/Utility/SecurityTest.php
index d48c6465d56..47b008de75a 100644
--- a/tests/TestCase/Utility/SecurityTest.php
+++ b/tests/TestCase/Utility/SecurityTest.php
@@ -16,6 +16,7 @@
  */
 namespace Cake\Test\TestCase\Utility;
 
+use Cake\Core\Configure;
 use Cake\TestSuite\TestCase;
 use Cake\Utility\Crypto\OpenSsl;
 use Cake\Utility\Security;
@@ -106,6 +107,33 @@ public function testEncryptDecrypt(): void
         $this->assertSame($txt, Security::decrypt($result, $key));
     }
 
+    /**
+     * Test encrypt/decrypt with raw key feature.
+     *
+     * Raw keys give results that are more quantum resistant.
+     */
+    public function testEncryptDecryptRawKey(): void
+    {
+        Configure::write('Security.encryptWithRawKey', true);
+
+        $txt = 'The quick brown fox';
+        $key = 'This key is longer than 32 bytes long.';
+        $result = Security::encrypt($txt, $key);
+        $this->assertNotEquals($txt, $result, 'Should be encrypted.');
+        $this->assertNotEquals($result, Security::encrypt($txt, $key), 'Each result is unique.');
+        $this->assertSame($txt, Security::decrypt($result, $key));
+
+        Configure::write('Security.encryptWithRawKey', false);
+
+        $oldKeyResult = Security::encrypt($txt, $key);
+        $this->assertNotEquals($txt, $oldKeyResult, 'Should be encrypted.');
+        $this->assertSame($txt, Security::decrypt($oldKeyResult, $key));
+        $this->assertNull(
+            Security::decrypt($result, $key),
+            'value encrypted with new key cannot be decrypted with old',
+        );
+    }
+
     /**
      * Test that changing the key causes decryption to fail.
      */
diff --git a/tests/TestCase/Utility/TextTest.php b/tests/TestCase/Utility/TextTest.php
index 759dfa83949..d4a81cd642d 100644
--- a/tests/TestCase/Utility/TextTest.php
+++ b/tests/TestCase/Utility/TextTest.php
@@ -1923,4 +1923,77 @@ public function testSubstr(): void
         $this->assertSame('&#x3044;&#x3046;&#x3048;', $substr($text, -4, -1, ['html' => true, 'trimWidth' => true]));
         $this->assertSame('&#x3044;&#x3046;&#x3048;', $substr($text, -4, -2, ['html' => true, 'trimWidth' => true]));
     }
+
+    /**
+     * Data provider for testMask()
+     *
+     * @return array<string, array>
+     */
+    public static function maskProvider(): array
+    {
+        return [
+            'mask single character string' => ['a', 0, null, '*', '*'],
+            'mask first N chars (credit card)' => ['4111111111111234', 0, 12, '*', '************1234'],
+            'mask mid-string with length' => ['Hello World', 2, 4, '*', 'He****World'],
+            'mask from offset to end' => ['sk_live_abc123', 8, null, '*', 'sk_live_******'],
+            'mask entire string' => ['secret', 0, null, 'x', 'xxxxxx'],
+            'offset < 0 and length = null' => ['sk_live_abc123xyz', -5, null, '*', 'sk_live_abc1*****'],
+            'offset < 0 and length <= stringLength' => ['taylor@example.com', -13, 4, '*', 'taylo****ample.com'],
+            'offset << 0 and length = null' => ['ilovecakephp', -99, null, '*', '************'],
+            'offset << 0 and length <= stringLength' => ['ilovecakephp', -99, 3, '*', '***vecakephp'],
+            'offset = stringLength' => ['hello', 5, null, '*', 'hello'],
+            'offset > stringLength' => ['hello', 999, null, '*', 'hello'],
+            'length > stringLength' => ['hello', 3, 100, '*', 'hel**'],
+            'length = 0' => ['hello', 2, 0, '*', 'hello'],
+            'empty string' => ['', 0, null, '*', ''],
+            'multibyte string masked mid' => ['こんにちは', 1, 3, '*', 'こ***は'],
+            'multibyte string masked full' => ['こんにちは', 0, null, 'x', 'xxxxx'],
+            'multibyte negative offset' => ['こんにちは', -2, null, '*', 'こんに**'],
+            'multibyte mask character' => ['hello', 1, 3, 'ক', 'hকককo'],
+        ];
+    }
+
+    /**
+     * testMask method
+     *
+     * @param string $string Input String
+     * @param int $offset Start position
+     * @param int|null $length Length of the masked portion
+     * @param string $maskCharacter Mask character
+     * @param string $expected Expected string
+     */
+    #[DataProvider('maskProvider')]
+    public function testMask(string $string, int $offset, ?int $length, string $maskCharacter, string $expected): void
+    {
+        $result = Text::mask($string, $offset, $length, $maskCharacter);
+        $this->assertSame($expected, $result);
+    }
+
+    /**
+     * Data provider for testMaskThrowsOnInvalidMaskCharacter()
+     *
+     * @return array<string, array>
+     */
+    public static function maskInvalidCharacterProvider(): array
+    {
+        return [
+            'empty mask' => ['ilovecakephp', 0, 3, ''],
+            'multi-char mask' => ['ilovecakephp', 0, 3, '**'],
+        ];
+    }
+
+    /**
+     * testMaskThrowsOnInvalidMaskCharacter method
+     *
+     * @param string $string Input String
+     * @param int $offset Start position
+     * @param int|null $length Length of the masked portion
+     * @param string $maskCharacter Mask character
+     */
+    #[DataProvider('maskInvalidCharacterProvider')]
+    public function testMaskThrowsOnInvalidMaskCharacter(string $string, int $offset, ?int $length, string $maskCharacter): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+        Text::mask($string, $offset, $length, $maskCharacter);
+    }
 }
diff --git a/tests/TestCase/View/Helper/FormHelperTest.php b/tests/TestCase/View/Helper/FormHelperTest.php
index 86db938309a..5b68b4ad9eb 100644
--- a/tests/TestCase/View/Helper/FormHelperTest.php
+++ b/tests/TestCase/View/Helper/FormHelperTest.php
@@ -567,6 +567,69 @@ public function testControlTemplateVars(): void
         $this->assertHtml($expected, $result);
     }
 
+    /**
+     * Test that `{{inputId}}` template variable is available in inputContainer template.
+     */
+    public function testControlInputIdTemplateVar(): void
+    {
+        $result = $this->Form->control('title', [
+            'templates' => [
+                'inputContainer' => '<div class="input {{type}}" data-input-id="{{inputId}}">{{content}}</div>',
+            ],
+        ]);
+        $this->assertStringContainsString('data-input-id="title"', $result);
+
+        // Test nested field name
+        $result = $this->Form->control('User.email', [
+            'templates' => [
+                'inputContainer' => '<div class="input {{type}}" data-input-id="{{inputId}}">{{content}}</div>',
+            ],
+        ]);
+        $this->assertStringContainsString('data-input-id="user-email"', $result);
+
+        // Test deeply nested field name
+        $result = $this->Form->control('User.address.city', [
+            'templates' => [
+                'inputContainer' => '<div class="input {{type}}" data-input-id="{{inputId}}">{{content}}</div>',
+            ],
+        ]);
+        $this->assertStringContainsString('data-input-id="user-address-city"', $result);
+    }
+
+    /**
+     * Test that `{{inputId}}` template variable is available in error template.
+     */
+    public function testErrorInputIdTemplateVar(): void
+    {
+        $this->article['errors'] = [
+            'title' => ['error message'],
+        ];
+        $this->Form->create($this->article);
+
+        $result = $this->Form->control('title', [
+            'templates' => [
+                'error' => '<div class="error" aria-describedby="{{inputId}}">{{content}}</div>',
+            ],
+        ]);
+        $this->assertStringContainsString('aria-describedby="title"', $result);
+        $this->assertStringContainsString('error message', $result);
+
+        // Test nested field name
+        $this->article['errors'] = [
+            'author' => [
+                'name' => ['Author name is required'],
+            ],
+        ];
+        $this->Form->create($this->article);
+
+        $result = $this->Form->control('author.name', [
+            'templates' => [
+                'error' => '<div class="error" aria-describedby="{{inputId}}">{{content}}</div>',
+            ],
+        ]);
+        $this->assertStringContainsString('aria-describedby="author-name"', $result);
+    }
+
     /**
      * Test ensuring template variables work in template files loaded
      * during control().
@@ -3940,6 +4003,37 @@ public function testEnumOptionsDeprecationMessage(): void
         });
     }
 
+    /**
+     * Test enumOptions() returns correct value => label mapping for backed enums.
+     */
+    public function testEnumOptions(): void
+    {
+        // Basic backed enum without EnumLabelInterface - labels from humanized case names
+        $result = $this->Form->enumOptions(ArticleStatus::class);
+        $expected = [
+            'Y' => 'Published',
+            'N' => 'Unpublished',
+        ];
+        $this->assertSame($expected, $result);
+
+        // Enum implementing EnumLabelInterface - labels from label() method
+        $result = $this->Form->enumOptions(ArticleStatusLabelInterface::class);
+        $expected = [
+            'Y' => 'Is Published',
+            'N' => 'Is Unpublished',
+        ];
+        $this->assertSame($expected, $result);
+
+        // Integer-backed enum implementing EnumLabelInterface
+        $result = $this->Form->enumOptions(Priority::class);
+        $expected = [
+            1 => 'Is Low',
+            2 => 'Is Medium',
+            3 => 'Is High',
+        ];
+        $this->assertSame($expected, $result);
+    }
+
     /**
      * testControlWithNonStandardPrimaryKeyMakesHidden method
      *
diff --git a/tests/test_app/Plugin/TestPlugin/src/Command/Helper/ExampleHelper.php b/tests/test_app/Plugin/TestPlugin/src/Console/Helper/ExampleHelper.php
similarity index 84%
rename from tests/test_app/Plugin/TestPlugin/src/Command/Helper/ExampleHelper.php
rename to tests/test_app/Plugin/TestPlugin/src/Console/Helper/ExampleHelper.php
index 75a522c531c..f486d809b6e 100644
--- a/tests/test_app/Plugin/TestPlugin/src/Command/Helper/ExampleHelper.php
+++ b/tests/test_app/Plugin/TestPlugin/src/Console/Helper/ExampleHelper.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 
-namespace TestPlugin\Command\Helper;
+namespace TestPlugin\Console\Helper;
 
 use Cake\Console\Helper;
 
diff --git a/tests/test_app/TestApp/Command/Helper/CommandHelper.php b/tests/test_app/TestApp/Console/Helper/CommandHelper.php
similarity index 86%
rename from tests/test_app/TestApp/Command/Helper/CommandHelper.php
rename to tests/test_app/TestApp/Console/Helper/CommandHelper.php
index 694b7029e8d..0e2eea3c265 100644
--- a/tests/test_app/TestApp/Command/Helper/CommandHelper.php
+++ b/tests/test_app/TestApp/Console/Helper/CommandHelper.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 
-namespace TestApp\Command\Helper;
+namespace TestApp\Console\Helper;
 
 use Cake\Console\Helper;
 
diff --git a/tests/test_app/TestApp/Command/Helper/SimpleHelper.php b/tests/test_app/TestApp/Console/Helper/SimpleHelper.php
similarity index 86%
rename from tests/test_app/TestApp/Command/Helper/SimpleHelper.php
rename to tests/test_app/TestApp/Console/Helper/SimpleHelper.php
index b8f15e122cd..204355bdfc4 100644
--- a/tests/test_app/TestApp/Command/Helper/SimpleHelper.php
+++ b/tests/test_app/TestApp/Console/Helper/SimpleHelper.php
@@ -1,7 +1,7 @@
 <?php
 declare(strict_types=1);
 
-namespace TestApp\Command\Helper;
+namespace TestApp\Console\Helper;
 
 use Cake\Console\Helper;
 
diff --git a/tests/test_app/TestApp/Controller/DependenciesController.php b/tests/test_app/TestApp/Controller/DependenciesController.php
index 523420d340e..b77fd69d008 100644
--- a/tests/test_app/TestApp/Controller/DependenciesController.php
+++ b/tests/test_app/TestApp/Controller/DependenciesController.php
@@ -3,10 +3,13 @@
 
 namespace TestApp\Controller;
 
+use Cake\Controller\Attribute\Enum\RequestToDtoSource;
+use Cake\Controller\Attribute\RequestToDto;
 use Cake\Controller\Controller;
 use Cake\Event\EventManagerInterface;
 use Cake\Http\ServerRequest;
 use stdClass;
+use TestApp\Dto\RequestDataDto;
 use TestApp\ReflectionDependency;
 
 /**
@@ -92,6 +95,34 @@ public function requiredDep(stdClass $dep, $any = null, ?string $str = null)
         return $this->response->withStringBody(json_encode(compact('dep', 'any', 'str')));
     }
 
+    public function requestDto(
+        #[RequestToDto]
+        RequestDataDto $dto,
+    ) {
+        return $this->response->withStringBody(json_encode($dto->toArray()));
+    }
+
+    public function requestDtoBody(
+        #[RequestToDto(source: RequestToDtoSource::Body)]
+        RequestDataDto $dto,
+    ) {
+        return $this->response->withStringBody(json_encode($dto->toArray()));
+    }
+
+    public function requestDtoQuery(
+        #[RequestToDto(source: RequestToDtoSource::Query)]
+        RequestDataDto $dto,
+    ) {
+        return $this->response->withStringBody(json_encode($dto->toArray()));
+    }
+
+    public function requestDtoRequest(
+        #[RequestToDto(source: RequestToDtoSource::Request)]
+        RequestDataDto $dto,
+    ) {
+        return $this->response->withStringBody(json_encode($dto->toArray()));
+    }
+
     /**
      * @return \Cake\Http\Response
      */
diff --git a/tests/test_app/TestApp/Dto/RequestDataDto.php b/tests/test_app/TestApp/Dto/RequestDataDto.php
new file mode 100644
index 00000000000..fe9ede89abc
--- /dev/null
+++ b/tests/test_app/TestApp/Dto/RequestDataDto.php
@@ -0,0 +1,31 @@
+<?php
+declare(strict_types=1);
+
+namespace TestApp\Dto;
+
+class RequestDataDto
+{
+    /**
+     * @param array<string, mixed> $data
+     */
+    public function __construct(private readonly array $data)
+    {
+    }
+
+    /**
+     * @param array<string, mixed> $data
+     * @return static
+     */
+    public static function createFromArray(array $data): self
+    {
+        return new self($data);
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function toArray(): array
+    {
+        return $this->data;
+    }
+}