angular · clydin · Aug 14, 2026 · Aug 13, 2026
diff --git a/packages/angular/build/src/builders/application/i18n.ts b/packages/angular/build/src/builders/application/i18n.ts
@@ -8,6 +8,7 @@
 
 import { BuilderContext } from '@angular-devkit/architect';
 import type { Metafile } from 'esbuild';
+import { readFile } from 'node:fs/promises';
 import { join } from 'node:path';
 import {
   ExecutionResult,
@@ -18,6 +19,7 @@ import { I18nInliner } from '../../tools/esbuild/i18n-inliner';
 import { maxWorkers } from '../../utils/environment-options';
 import { loadTranslations } from '../../utils/i18n-options';
 import { createTranslationLoader } from '../../utils/load-translations';
+import { createProjectResolver } from '../../utils/resolve-project';
 import { executePostBundleSteps } from './execute-post-bundle';
 import { NormalizedApplicationBuildOptions, getLocaleBaseHref } from './options';
 
@@ -48,6 +50,7 @@ export async function inlineI18n(
       outputFiles: executionResult.outputFiles,
       shouldOptimize: optimizationOptions.scripts,
       persistentCachePath: cacheOptions.enabled ? cacheOptions.path : undefined,
+      localizeVersion: i18nOptions.localizeVersion,
     },
     maxWorkers,
   );
@@ -72,10 +75,21 @@ export async function inlineI18n(
 
   try {
     for (const locale of i18nOptions.inlineLocales) {
+      const localeDescription = i18nOptions.locales[locale];
+      let translationIntegrity: string | undefined = '';
+      for (const file of localeDescription.files) {
+        if (!file.integrity) {
+          translationIntegrity = undefined;
+          break;
+        }
+        translationIntegrity += (translationIntegrity ? '|' : '') + file.integrity;
+      }
+
       // A locale specific set of files is returned from the inliner.
       const localeInlineResult = await inliner.inlineForLocale(
         locale,
-        i18nOptions.locales[locale].translation,
+        localeDescription.translation,
+        translationIntegrity,
       );
       const localeOutputFiles = localeInlineResult.outputFiles;
       inlineResult.errors.push(...localeInlineResult.errors);
@@ -176,6 +190,15 @@ export async function loadActiveTranslations(
   context: BuilderContext,
   i18n: NormalizedApplicationBuildOptions['i18nOptions'],
 ) {
+  if (!i18n.localizeVersion) {
+    try {
+      const projectResolve = createProjectResolver(context.workspaceRoot);
+      const manifestPath = projectResolve('@angular/localize/package.json');
+      const manifest = JSON.parse(await readFile(manifestPath, 'utf-8')) as { version?: string };
+      i18n.localizeVersion = manifest.version;
+    } catch {}
+  }
+
   // Load locale data and translations (if present)
   let loader;
   for (const [locale, desc] of Object.entries(i18n.locales)) {

diff --git a/packages/angular/build/src/tools/esbuild/i18n-inliner.ts b/packages/angular/build/src/tools/esbuild/i18n-inliner.ts
@@ -42,6 +42,7 @@ export interface I18nInlinerOptions {
   outputFiles: BuildOutputFile[];
   shouldOptimize?: boolean;
   persistentCachePath?: string;
+  localizeVersion?: string;
 }
 
 /**
@@ -131,11 +132,13 @@ export class I18nInliner {
    * of the localize function keyword.
    * @param locale The string representing the locale to inline.
    * @param translation The translation messages to use when inlining.
+   * @param translationIntegrity An optional integrity value for the translation messages to use for caching.
    * @returns A promise that resolves to an array of OutputFiles representing a translated result.
    */
   async inlineForLocale(
     locale: string,
     translation: Record<string, unknown> | undefined,
+    translationIntegrity?: string,
   ): Promise<{ outputFiles: BuildOutputFile[]; errors: string[]; warnings: string[] }> {
     await this.initCache();
 
@@ -161,7 +164,13 @@ export class I18nInliner {
         // of bytes. Hashing the options directly would re-hash the full set of messages, which
         // can be several megabytes, once for every file.
         fileCacheKeyBase ??= calculateHash(
-          JSON.stringify({ locale, translation, missingTranslation, shouldOptimize }),
+          JSON.stringify({
+            locale,
+            translation: translationIntegrity ?? translation,
+            missingTranslation,
+            shouldOptimize,
+            localizeVersion: this.options.localizeVersion,
+          }),
         );
 
         // NOTE: If additional options are added, this may need to be updated.

diff --git a/packages/angular/build/src/tools/esbuild/i18n-inliner_spec.ts b/packages/angular/build/src/tools/esbuild/i18n-inliner_spec.ts
@@ -307,4 +307,37 @@ describe('I18nInliner', () => {
       'Malformed escape sequence in $localize template literal in file "main.js".',
     ]);
   });
+
+  it('inlines the translations of a locale when translationIntegrity is provided', async () => {
+    const { outputFiles, errors, warnings } = await createInliner([
+      browserFile('main.js', GREETING_SOURCE),
+    ]).inlineForLocale('fr', { greeting: translationFor('Bonjour') }, 'sha256-test-integrity');
+
+    expect(errors).toEqual([]);
+    expect(warnings).toEqual([]);
+    expect(findFile(outputFiles, 'main.js').text).toContain('"Bonjour"');
+    expect(findFile(outputFiles, 'main.js').text).not.toContain('$localize');
+  });
+
+  it('inlines the translations of a locale when localizeVersion is configured in options', async () => {
+    inliner = new I18nInliner(
+      {
+        missingTranslation: 'warning',
+        outputFiles: [browserFile('main.js', GREETING_SOURCE)],
+        localizeVersion: '20.2.0',
+      },
+      1,
+    );
+
+    const { outputFiles, errors, warnings } = await inliner.inlineForLocale(
+      'fr',
+      { greeting: translationFor('Bonjour') },
+      'sha256-test-integrity',
+    );
+
+    expect(errors).toEqual([]);
+    expect(warnings).toEqual([]);
+    expect(findFile(outputFiles, 'main.js').text).toContain('"Bonjour"');
+    expect(findFile(outputFiles, 'main.js').text).not.toContain('$localize');
+  });
 });
diff --git a/packages/angular/build/src/utils/i18n-options.ts b/packages/angular/build/src/utils/i18n-options.ts
@@ -28,6 +28,7 @@ export interface I18nOptions {
   flatOutput?: boolean;
   readonly shouldInline: boolean;
   hasDefinedSourceLocale?: boolean;
+  localizeVersion?: string;
 }
 
 function normalizeTranslationFileOption(