Export any serializable PHP value as a pure array — and rebuild it back into the original object graph. Also doubles as a native accelerator for Symfony's VarExporter\DeepCloner.

The extension exposes two functions:

function deepclone_to_array(mixed $value): array;
function deepclone_from_array(array $data): mixed;

deepclone_to_array() walks any PHP value graph — objects, arrays, references, closures, enums, internal types — and returns a payload that contains only scalars and nested arrays: no objects, no resources, no surprises. Pass that payload to anything that handles plain PHP arrays — json_encode(), var_export(), APCu, igbinary, MessagePack, an HTTP body, a cache backend.

deepclone_from_array() does the reverse: feed it the payload and it rebuilds the original graph, preserving object identity, internal references, private properties, __wakeup / __unserialize semantics, and so on.

The wire format is the one used by Symfony's VarExporter\DeepCloner::toArray() / ::fromArray(). The two implementations produce identical payloads, so you can produce on one side and consume on the other.

• A pure-array form for any value, even ones that can't normally be JSON-encoded (objects with private state, cycles, references, closures over named methods, …). Once a graph is in array form it can travel through any serializer or cache layer that doesn't speak PHP objects.
• Identity & reference preservation: shared subgraphs stay shared, hard references stay live, cycles round-trip cleanly. Unlike json_encode() or var_export(), no information is lost on the way out.
• 4–5× faster than the pure-PHP DeepCloner implementation on toArray() and end-to-end deepClone().
• On par with unserialize(serialize($value)), while preserving copy-on-write for strings and scalar arrays — so memory usage stays low when the input is mostly immutable.

• PHP 8.2 or later (NTS or ZTS, 64-bit and 32-bit)
• ext-reflection and ext-spl (always present in stock PHP builds)

PIE is the modern installer for PHP extensions:

pie install symfony/deepclone

On Linux and macOS, PIE compiles from source. On Windows, PIE downloads the prebuilt DLL matching your PHP version, architecture, and TS/NTS flavor from the GitHub release — no MSVC or PHP SDK required.

Then enable the extension in your php.ini:

extension=deepclone

git clone https://github.com/symfony/php-ext-deepclone.git
cd php-ext-deepclone
phpize
./configure --enable-deepclone
make
make test
sudo make install

Then enable in php.ini as above.

$graph = new MyComplexObject(/* ... */);

$payload = deepclone_to_array($graph);   // pure array
$copy    = deepclone_from_array($payload); // fresh deep copy

If you have symfony/var-exporter installed, just load the extension — Symfony's DeepCloner automatically picks it up at file-load time. No code change needed:

use Symfony\Component\VarExporter\DeepCloner;

$copy = DeepCloner::deepClone($graph); // 4–5× faster with the extension loaded

Both functions throw \Exception (with a stable code) when the input cannot be processed. The exception message is the bare class or type name; PHP-side wrappers (e.g. Symfony's NativeDeepClonerTrait) translate them into domain-specific exception types.

deepclone_from_array() additionally throws \ValueError on malformed input.

• PHP versions: 8.2, 8.3, 8.4, 8.5 — tested on each in CI.
• Builds: NTS and ZTS, on Linux, macOS, and Windows.
• Wire format: stable across patch releases. Any change to the wire format in a way that would break interoperability with the PHP DeepCloner will be a minor (0.x) bump pre-1.0 and a major bump post-1.0.

This extension is a drop-in C accelerator for the PHP code at Symfony\Component\VarExporter\DeepCloner. It does not replace the component — Symfony's pure-PHP path remains the reference implementation, the source of truth for the wire format, and the fallback when the extension is not loaded. Loading the extension is purely opt-in and transparent.

Released under the MIT license.