Use `i18next` for UI strings and add new `injectTranslations` plugin callback (#1923)

Co-authored-by: Chris Swithinbank <357379+delucis@users.noreply.github.com>
Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>
Co-authored-by: HiDeoo <494699+HiDeoo@users.noreply.github.com>

58 files changed, 925 insertions, 282 deletions

diff --git a/.changeset/cool-experts-sort.md b/.changeset/cool-experts-sort.md
new file mode 100644
index 00000000..6de9fd8c
--- /dev/null
+++ b/.changeset/cool-experts-sort.md
@@ -0,0 +1,19 @@
+---
+'@astrojs/starlight': minor
+---
+
+Overhauls the built-in localization system which is now powered by the [`i18next`](https://www.i18next.com/) library and available to use anywhere in your documentation website.
+
+See the [“Using UI translations”](https://starlight.astro.build/guides/i18n/#using-ui-translations) guide to learn more about how to access built-in UI labels or your own custom strings in your project. Plugin authors can also use the new [`injectTranslations()`](https://starlight.astro.build/reference/plugins/#injecttranslations) helper to add or update translation strings.
+
+⚠️ **BREAKING CHANGE:** The `Astro.props.labels` props has been removed from the props passed down to custom component overrides.
+
+If you are relying on `Astro.props.labels` (for example to read a built-in UI label), you will need to update your code to use the new [`Astro.locals.t()`](https://starlight.astro.build/guides/i18n/#using-ui-translations) helper instead.
+
+```astro
+---
+import type { Props } from '@astrojs/starlight/props';
+// The `search.label` UI label for this page’s language:
+const searchLabel = Astro.locals.t('search.label');
+---
+```
diff --git a/.changeset/eighty-beds-attack.md b/.changeset/eighty-beds-attack.md
new file mode 100644
index 00000000..000fa3e9
--- /dev/null
+++ b/.changeset/eighty-beds-attack.md
@@ -0,0 +1,11 @@
+---
+'@astrojs/starlight-docsearch': minor
+---
+
+⚠️ **BREAKING CHANGE:** The minimum supported version of Starlight is now 0.28.0
+
+Please use the `@astrojs/upgrade` command to upgrade your project:
+
+```sh
+npx @astrojs/upgrade
+```
diff --git a/.changeset/thirty-dodos-drop.md b/.changeset/thirty-dodos-drop.md
new file mode 100644
index 00000000..4fef44db
--- /dev/null
+++ b/.changeset/thirty-dodos-drop.md
@@ -0,0 +1,11 @@
+---
+'@astrojs/starlight': minor
+---
+
+⚠️ **BREAKING CHANGE:** The minimum supported version of Astro is now 4.14.0
+
+Please update Astro and Starlight together:
+
+```sh
+npx @astrojs/upgrade
+```
diff --git a/.npmrc b/.npmrc
index 901b4e86..11cb30ee 100644
--- a/.npmrc
+++ b/.npmrc
@@ -1,3 +1,4 @@
 prefer-workspace-packages=true
 link-workspace-packages=true
 shell-emulator=true
+auto-install-peers=false
diff --git a/docs/src/content/docs/guides/i18n.mdx b/docs/src/content/docs/guides/i18n.mdx
index 2fe235b2..a320fbab 100644
--- a/docs/src/content/docs/guides/i18n.mdx
+++ b/docs/src/content/docs/guides/i18n.mdx
@@ -276,6 +276,118 @@ export const collections = {
 
 Learn more about content collection schemas in [“Defining a collection schema”](https://docs.astro.build/en/guides/content-collections/#defining-a-collection-schema) in the Astro docs.
 
+## Using UI translations
+
+You can access Starlight’s [built-in UI strings](/guides/i18n/#translate-starlights-ui) as well as [user-defined](/guides/i18n/#extend-translation-schema), and [plugin-provided](/reference/plugins/#injecttranslations) UI strings through a unified API powered by [i18next](https://www.i18next.com/).
+This includes support for features like [interpolation](https://www.i18next.com/translation-function/interpolation) and [pluralization](https://www.i18next.com/translation-function/plurals).
+
+In Astro components, this API is available as part of the [global `Astro` object](https://docs.astro.build/en/reference/api-reference/#astrolocals) as `Astro.locals.t`:
+
+```astro title="example.astro"
+<p dir={Astro.locals.t.dir()}>
+	{Astro.locals.t('404.text')}
+</p>
+```
+
+You can also use the API in [endpoints](https://docs.astro.build/en/guides/endpoints/), where the `locals` object is available as part of the [endpoint context](https://docs.astro.build/en/reference/api-reference/#contextlocals):
+
+```ts title="src/pages/404.ts"
+export const GET = (context) => {
+	return new Response(context.locals.t('404.text'));
+};
+```
+
+### Rendering a UI string
+
+Render UI strings using the `locals.t()` function.
+This is an instance of i18next’s `t()` function, which takes a UI string key as its first argument and returns the corresponding translation for the current language.
+
+For example, given a custom translation file with the following content:
+
+```json title="src/content/i18n/en.json"
+{
+	"link.astro": "Astro documentation",
+	"link.astro.custom": "Astro documentation for {{feature}}"
+}
+```
+
+The first UI string can be rendered by passing `'link.astro'` to the `t()` function:
+
+```astro {3}
+<!-- src/components/Example.astro -->
+<a href="https://docs.astro.build/">
+	{Astro.locals.t('link.astro')}
+</a>
+<!-- Renders: <a href="...">Astro documentation</a> -->
+```
+
+The second UI string uses i18next’s [interpolation syntax](https://www.i18next.com/translation-function/interpolation) for the `{{feature}}` placeholder.
+The value for `feature` must be set in an options object passed as the second argument to `t()`:
+
+```astro {3}
+<!-- src/components/Example.astro -->
+<a href="https://docs.astro.build/en/guides/astro-db/">
+	{Astro.locals.t('link.astro.custom', { feature: 'Astro DB' })}
+</a>
+<!-- Renders: <a href="...">Astro documentation for Astro DB</a> -->
+```
+
+See the [i18next documentation](https://www.i18next.com/overview/api#t) for more information on how to use the `t()` function with interpolation, formatting, and more.
+
+### Advanced APIs
+
+#### `t.all()`
+
+The `locals.t.all()` function returns an object containing all UI strings available for the current locale.
+
+```astro
+---
+// src/components/Example.astro
+const allStrings = Astro.locals.t.all();
+//    ^
+//    {
+//      "skipLink.label": "Skip to content",
+//      "search.label": "Search",
+//      …
+//    }
+---
+```
+
+#### `t.exists()`
+
+To check if a translation key exists for a locale, use the `locals.t.exists()` function with the translation key as first argument.
+Pass an optional second argument if you need to override the current locale.
+
+```astro
+---
+// src/components/Example.astro
+const keyExistsInCurrentLocale = Astro.locals.t.exists('a.key');
+//    ^ true
+const keyExistsInFrench = Astro.locals.t.exists('another.key', { lng: 'fr' });
+//    ^ false
+---
+```
+
+See the [`exists()` reference in the i18next documentation](https://www.i18next.com/overview/api#exists) for more information.
+
+#### `t.dir()`
+
+The `locals.t.dir()` function returns the text direction of the current or a specific locale.
+
+```astro
+---
+// src/components/Example.astro
+const currentDirection = Astro.locals.t.dir();
+//    ^
+//    'ltr'
+const arabicDirection = Astro.locals.t.dir('ar');
+//    ^
+//    'rtl'
+---
+```
+
+See the [`dir()` reference in the i18next documentation](https://www.i18next.com/overview/api#dir) for more information.
+
 ## Accessing the current locale
 
 You can use [`Astro.currentLocale`](https://docs.astro.build/en/reference/api-reference/#astrocurrentlocale) to read the current locale in `.astro` components.
diff --git a/docs/src/content/docs/reference/overrides.md b/docs/src/content/docs/reference/overrides.md
index 9293654b..8e5ed012 100644
--- a/docs/src/content/docs/reference/overrides.md
+++ b/docs/src/content/docs/reference/overrides.md
@@ -148,12 +148,6 @@ JavaScript `Date` object representing when this page was last updated if enabled
 
 `URL` object for the address where this page can be edited if enabled.
 
-#### `labels`
-
-**Type:** `Record<string, string>`
-
-An object containing UI strings localized for the current page. See the [“Translate Starlight’s UI”](/guides/i18n/#translate-starlights-ui) guide for a list of all the available keys.
-
 ---
 
 ## Components
diff --git a/docs/src/content/docs/reference/plugins.md b/docs/src/content/docs/reference/plugins.md
index 7f44f60b..e22d146a 100644
--- a/docs/src/content/docs/reference/plugins.md
+++ b/docs/src/content/docs/reference/plugins.md
@@ -27,6 +27,7 @@ interface StarlightPlugin {
       command: 'dev' | 'build' | 'preview';
       isRestart: boolean;
       logger: AstroIntegrationLogger;
+      injectTranslations: (Record<string, Record<string, string>>) => void;
     }) => void | Promise<void>;
   };
 }
@@ -161,3 +162,71 @@ The example above will log a message that includes the provided info message:
 ```shell
 [long-process-plugin] Starting long process…
 ```
+
+#### `injectTranslations`
+
+**type:** `(translations: Record<string, Record<string, string>>) => void`
+
+A callback function to add or update translation strings used in Starlight’s [localization APIs](/guides/i18n/#using-ui-translations).
+
+In the following example, a plugin injects translations for a custom UI string named `myPlugin.doThing` for the `en` and `fr` locales:
+
+```ts {6-13} /(injectTranslations)[^(]/
+// plugin.ts
+export default {
+  name: 'plugin-with-translations',
+  hooks: {
+    setup({ injectTranslations }) {
+      injectTranslations({
+        en: {
+          'myPlugin.doThing': 'Do the thing',
+        },
+        fr: {
+          'myPlugin.doThing': 'Faire le truc',
+        },
+      });
+    },
+  },
+};
+```
+
+To use the injected translations in your plugin UI, follow the [“Using UI translations” guide](/guides/i18n/#using-ui-translations).
+
+Types for a plugin’s injected translation strings are generated automatically in a user’s project, but are not yet available when working in your plugin’s codebase.
+To type the `locals.t` object in the context of your plugin, declare the following global namespaces in a TypeScript declaration file:
+
+```ts
+// env.d.ts
+declare namespace App {
+  type StarlightLocals = import('@astrojs/starlight').StarlightLocals;
+  // Define the `locals.t` object in the context of a plugin.
+  interface Locals extends StarlightLocals {}
+}
+
+declare namespace StarlightApp {
+  // Define the additional plugin translations in the `I18n` interface.
+  interface I18n {
+    'myPlugin.doThing': string;
+  }
+}
+```
+
+You can also infer the types for the `StarlightApp.I18n` interface from a source file if you have an object containing your translations.
+
+For example, given the following source file:
+
+```ts title="ui-strings.ts"
+export const UIStrings = {
+  en: { 'myPlugin.doThing': 'Do the thing' },
+  fr: { 'myPlugin.doThing': 'Faire le truc' },
+};
+```
+
+The following declaration would infer types from the English keys in the source file:
+
+```ts title="env.d.ts"
+declare namespace StarlightApp {
+  type UIStrings = typeof import('./ui-strings').UIStrings.en;
+  interface I18n extends UIStrings {}
+}
+```
diff --git a/package.json b/package.json
index e328ac87..41c2ad50 100644
--- a/package.json
+++ b/package.json
@@ -42,5 +42,13 @@
       "limit": "14.5 kB",
       "gzip": true
     }
-  ]
+  ],
+  "pnpm": {
+    "peerDependencyRules": {
+      "ignoreMissing": [
+        "@algolia/client-search",
+        "search-insights"
+      ]
+    }
+  }
 }
diff --git a/packages/docsearch/DocSearch.astro b/packages/docsearch/DocSearch.astro
index 12db6b46..467192af 100644
--- a/packages/docsearch/DocSearch.astro
+++ b/packages/docsearch/DocSearch.astro
@@ -4,8 +4,6 @@ import '@docsearch/css/dist/modal.css';
 import type docsearch from '@docsearch/js';
 import './variables.css';
 
-const { labels } = Astro.props;
-
 type DocSearchTranslationProps = Pick<
 	Parameters<typeof docsearch>[0],
 	'placeholder' | 'translations'
@@ -13,15 +11,18 @@ type DocSearchTranslationProps = Pick<
 
 const pick = (keyStart: string) =>
 	Object.fromEntries(
-		Object.entries(labels)
+		Object.entries(Astro.locals.t.all())
 			.filter(([key]) => key.startsWith(keyStart))
 			.map(([key, value]) => [key.replace(keyStart, ''), value])
 	);
 
 const docsearchTranslations: DocSearchTranslationProps = {
-	placeholder: labels['search.label'],
+	placeholder: Astro.locals.t('search.label'),
 	translations: {
-		button: { buttonText: labels['search.label'], buttonAriaLabel: labels['search.label'] },
+		button: {
+			buttonText: Astro.locals.t('search.label'),
+			buttonAriaLabel: Astro.locals.t('search.label'),
+		},
 		modal: {
 			searchBox: pick('docsearch.searchBox.'),
 			startScreen: pick('docsearch.startScreen.'),
@@ -34,7 +35,11 @@ const docsearchTranslations: DocSearchTranslationProps = {
 ---
 
 <sl-doc-search data-translations={JSON.stringify(docsearchTranslations)}>
-	<button type="button" class="DocSearch DocSearch-Button" aria-label={labels['search.label']}>
+	<button
+		type="button"
+		class="DocSearch DocSearch-Button"
+		aria-label={Astro.locals.t('search.label')}
+	>
 		<span class="DocSearch-Button-Container">
 			<svg width="20" height="20" class="DocSearch-Search-Icon" viewBox="0 0 20 20">
 				<path
@@ -45,7 +50,7 @@ const docsearchTranslations: DocSearchTranslationProps = {
 					stroke-linecap="round"
 					stroke-linejoin="round"></path>
 			</svg>
-			<span class="DocSearch-Button-Placeholder">{labels['search.label']}</span>
+			<span class="DocSearch-Button-Placeholder">{Astro.locals.t('search.label')}</span>
 		</span>
 		<span class="DocSearch-Button-Keys"></span>
 	</button>
diff --git a/packages/docsearch/package.json b/packages/docsearch/package.json
index d4ec221e..8826ac25 100644
--- a/packages/docsearch/package.json
+++ b/packages/docsearch/package.json
@@ -25,10 +25,13 @@
     "./schema": "./schema.ts"
   },
   "peerDependencies": {
-    "@astrojs/starlight": ">=0.14.0"
+    "@astrojs/starlight": ">=0.28.0"
   },
   "dependencies": {
     "@docsearch/css": "^3.6.0",
     "@docsearch/js": "^3.6.0"
+  },
+  "devDependencies": {
+    "@astrojs/starlight": "workspace:*"
   }
 }
diff --git a/packages/markdoc/package.json b/packages/markdoc/package.json
index 81e79cd8..8b5898c4 100644
--- a/packages/markdoc/package.json
+++ b/packages/markdoc/package.json
@@ -17,6 +17,8 @@
     "./components": "./components.ts"
   },
   "devDependencies": {
+    "@astrojs/markdoc": "^0.11.4",
+    "@astrojs/starlight": "workspace:*",
     "vitest": "^1.6.0"
   },
   "peerDependencies": {
diff --git a/packages/starlight/__tests__/basics/route-data.test.ts b/packages/starlight/__tests__/basics/route-data.test.ts
index d59ce013..f3293259 100644
--- a/packages/starlight/__tests__/basics/route-data.test.ts
+++ b/packages/starlight/__tests__/basics/route-data.test.ts
@@ -1,6 +1,7 @@
 import { expect, test, vi } from 'vitest';
 import { generateRouteData } from '../../utils/route-data';
 import { routes } from '../../utils/routing';
+import pkg from '../../package.json';
 
 vi.mock('astro:content', async () =>
 	(await import('../test-utils')).mockedAstroContent({
@@ -87,12 +88,24 @@ test('uses explicit last updated date from frontmatter', () => {
 	expect(data.lastUpdated).toEqual(route.entry.data.lastUpdated);
 });
 
-test('includes localized labels', () => {
+test('throws when accessing a label using the deprecated `labels` prop in pre v1 versions', () => {
+	const isPreV1 = pkg.version[0] === '0';
+
 	const route = routes[0]!;
 	const data = generateRouteData({
 		props: { ...route, headings: [{ depth: 1, slug: 'heading-1', text: 'Heading 1' }] },
 		url: new URL('https://example.com'),
 	});
-	expect(data.labels).toBeDefined();
-	expect(data.labels['skipLink.label']).toBe('Skip to content');
+
+	if (isPreV1) {
+		expect(() => data.labels['any']).toThrowErrorMatchingInlineSnapshot(`
+			"[AstroUserError]:
+				The \`labels\` prop in component overrides has been removed.
+			Hint:
+				Replace \`Astro.props.labels["any"]\` with \`Astro.locals.t("any")\` instead.
+				For more information see https://starlight.astro.build/guides/i18n/#using-ui-translations"
+		`);
+	} else {
+		expect(() => data.labels['any']).not.toThrow();
+	}
 });
diff --git a/packages/starlight/__tests__/basics/starlight-page-route-data.test.ts b/packages/starlight/__tests__/basics/starlight-page-route-data.test.ts
index 63ac6efd..c3510a65 100644
--- a/packages/starlight/__tests__/basics/starlight-page-route-data.test.ts
+++ b/packages/starlight/__tests__/basics/starlight-page-route-data.test.ts
@@ -467,13 +467,18 @@ test('hides the sidebar if the `hasSidebar` option is not specified and the spla
 	expect(data.hasSidebar).toBe(false);
 });
 
-test('includes localized labels', async () => {
+test('throws when accessing a label using the deprecated `labels` prop', async () => {
 	const data = await generateStarlightPageRouteData({
 		props: starlightPageProps,
 		url: starlightPageUrl,
 	});
-	expect(data.labels).toBeDefined();
-	expect(data.labels['skipLink.label']).toBe('Skip to content');
+	expect(() => data.labels['any']).toThrowErrorMatchingInlineSnapshot(`
+		"[AstroUserError]:
+			The \`labels\` prop in component overrides has been removed.
+		Hint:
+			Replace \`Astro.props.labels["any"]\` with \`Astro.locals.t("any")\` instead.
+			For more information see https://starlight.astro.build/guides/i18n/#using-ui-translations"
+	`);
 });
 
 test('uses provided edit URL if any', async () => {
diff --git a/packages/starlight/__tests__/basics/translations.test.ts b/packages/starlight/__tests__/basics/translations.test.ts
new file mode 100644
index 00000000..abada3e4
--- /dev/null
+++ b/packages/starlight/__tests__/basics/translations.test.ts
@@ -0,0 +1,149 @@
+import { describe, expect, test, vi } from 'vitest';
+import { useTranslations } from '../../utils/translations';
+import translations from '../../translations';
+
+describe('useTranslations()', () => {
+	test('includes localized UI strings', () => {
+		const t = useTranslations(undefined);
+		expect(t).toBeTypeOf('function');
+		expect(t('skipLink.label')).toBe('Skip to content');
+	});
+});
+
+describe('t()', async () => {
+	// The mocked user-defined translations are scoped to this `describe` block so that they do not
+	// affect other tests (`vi.mock` → `vi.doMock`).
+	vi.doMock('astro:content', async () =>
+		(await import('../test-utils')).mockedAstroContent({
+			i18n: [
+				[
+					'en',
+					{
+						'test.interpolation': '{{subject}} is {{adjective}}',
+						'test.dataModel': 'Powered by {{integration.name}}',
+						'test.escape': 'The tag is {{tag}}',
+						'test.unescape': 'The tag is {{- tag}}',
+						'test.currency': 'The price is {{price, currency(USD)}}',
+						'test.list': '{{subjects, list}} are awesome',
+						'test.count_one': '{{count}} project',
+						'test.count_other': '{{count}} projects',
+						'test.nesting1': '$t(test.nesting2) is nested',
+						'test.nesting2': 'this UI string',
+					},
+					// We do not strip unknown translations in this test so that user-defined translations can
+					// override plugin translations like it would in a real- world scenario were the plugin
+					// would have provided a custom schema to extend the translations.
+					{ stripUnknown: false },
+				],
+			],
+		})
+	);
+	// Reset the modules registry so that re-importing `../../utils/translations` re-evaluates the
+	// module and re-computes `useTranslations`. Re-importing the module is necessary because
+	// top-level imports cannot be re-evaluated.
+	vi.resetModules();
+	const { useTranslations } = await import('../../utils/translations');
+	const t = useTranslations(undefined);
+
+	test('supports using interpolation', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.interpolation', { subject: 'Starlight', adjective: 'amazing' })).toBe(
+			'Starlight is amazing'
+		);
+	});
+
+	test('supports using data models', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.dataModel', { integration: { name: 'Starlight' } })).toBe(
+			'Powered by Starlight'
+		);
+	});
+
+	test('escapes by default', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.escape', { tag: '<img />' })).toBe('The tag is &lt;img &#x2F;&gt;');
+	});
+
+	test('supports unescaped strings', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.unescape', { tag: '<img />' })).toBe('The tag is <img />');
+	});
+
+	test('supports currencies', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.currency', { price: 1000 })).toBe('The price is $1,000.00');
+	});
+
+	test('supports lists', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.list', { subjects: ['Astro', 'Starlight', 'Astro DB'] })).toBe(
+			'Astro, Starlight, and Astro DB are awesome'
+		);
+	});
+
+	test('supports counts', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.count', { count: 1 })).toBe('1 project');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.count', { count: 20 })).toBe('20 projects');
+	});
+
+	test('supports nesting', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a mocked translation key.
+		expect(t('test.nesting1')).toBe('this UI string is nested');
+	});
+
+	test('returns the UI string key if the translation is missing', () => {
+		expect(t).toBeTypeOf('function');
+		// @ts-expect-error - using a missing translation key.
+		expect(t('test.unknown')).toBe('test.unknown');
+	});
+});
+
+describe('t.all()', async () => {
+	// See the `t()` tests for an explanation of how the user-defined translations are mocked.
+	vi.doMock('astro:content', async () =>
+		(await import('../test-utils')).mockedAstroContent({
+			i18n: [['en', { 'test.foo': 'bar' }, { stripUnknown: false }]],
+		})
+	);
+	vi.resetModules();
+	const { useTranslations } = await import('../../utils/translations');
+	const t = useTranslations(undefined);
+
+	test('returns all translations including custom ones', () => {
+		expect(t.all).toBeTypeOf('function');
+		expect(t.all()).toEqual({ ...translations.en, 'test.foo': 'bar' });
+	});
+});
+
+describe('t.exists()', async () => {
+	// See the `t()` tests for an explanation of how the user-defined translations are mocked.
+	vi.doMock('astro:content', async () =>
+		(await import('../test-utils')).mockedAstroContent({
+			i18n: [['en', { 'test.foo': 'bar' }, { stripUnknown: false }]],
+		})
+	);
+	vi.resetModules();
+	const { useTranslations } = await import('../../utils/translations');
+	const t = useTranslations(undefined);
+
+	test('returns `true` for existing translations', () => {
+		expect(t.exists).toBeTypeOf('function');
+		expect(t.exists('skipLink.label')).toBe(true);
+		expect(t.exists('test.foo')).toBe(true);
+	});
+
+	test('returns `false` for unknown translations', () => {
+		expect(t.exists).toBeTypeOf('function');
+		expect(t.exists('test.unknown')).toBe(false);
+	});
+});
diff --git a/packages/starlight/__tests__/i18n-non-root-single-locale/route-data.test.ts b/packages/starlight/__tests__/i18n-non-root-single-locale/route-data.test.ts
deleted file mode 100644
index dbf5d354..00000000
--- a/packages/starlight/__tests__/i18n-non-root-single-locale/route-data.test.ts
+++ /dev/null
@@ -1,19 +0,0 @@
-import { expect, test, vi } from 'vitest';
-import { generateRouteData } from '../../utils/route-data';
-import { routes } from '../../utils/routing';
-
-vi.mock('astro:content', async () =>
-	(await import('../test-utils')).mockedAstroContent({
-		docs: [['fr/index.mdx', { title: 'Accueil' }]],
-	})
-);
-
-test('includes localized labels (fr)', () => {
-	const route = routes[0]!;
-	const data = generateRouteData({
-		props: { ...route, headings: [{ depth: 1, slug: 'heading-1', text: 'Heading 1' }] },
-		url: new URL('https://example.com'),
-	});
-	expect(data.labels).toBeDefined();
-	expect(data.labels['skipLink.label']).toBe('Aller au contenu');
-});
diff --git a/packages/starlight/__tests__/i18n-single-root-locale/route-data.test.ts b/packages/starlight/__tests__/i18n-single-root-locale/route-data.test.ts
deleted file mode 100644
index 654ba1b7..00000000
--- a/packages/starlight/__tests__/i18n-single-root-locale/route-data.test.ts
+++ /dev/null
@@ -1,19 +0,0 @@
-import { expect, test, vi } from 'vitest';
-import { generateRouteData } from '../../utils/route-data';
-import { routes } from '../../utils/routing';
-
-vi.mock('astro:content', async () =>
-	(await import('../test-utils')).mockedAstroContent({
-		docs: [['index.mdx', { title: 'Accueil' }]],
-	})
-);
-
-test('includes localized labels (fr)', () => {
-	const route = routes[0]!;
-	const data = generateRouteData({
-		props: { ...route, headings: [{ depth: 1, slug: 'heading-1', text: 'Heading 1' }] },
-		url: new URL('https://example.com'),
-	});
-	expect(data.labels).toBeDefined();
-	expect(data.labels['skipLink.label']).toBe('Aller au contenu');
-});
diff --git a/packages/starlight/__tests__/i18n/route-data.test.ts b/packages/starlight/__tests__/i18n/route-data.test.ts
deleted file mode 100644
index 57beed0c..00000000
--- a/packages/starlight/__tests__/i18n/route-data.test.ts
+++ /dev/null
@@ -1,32 +0,0 @@
-import { expect, test, vi } from 'vitest';
-import { generateRouteData } from '../../utils/route-data';
-import { routes } from '../../utils/routing';
-
-vi.mock('astro:content', async () =>
-	(await import('../test-utils')).mockedAstroContent({
-		docs: [
-			['fr/index.mdx', { title: 'Accueil' }],
-			['pt-br/index.mdx', { title: 'Pagina inicial' }],
-		],
-	})
-);
-
-test('includes localized labels (fr)', () => {
-	const route = routes[0]!;
-	const data = generateRouteData({
-		props: { ...route, headings: [{ depth: 1, slug: 'heading-1', text: 'Heading 1' }] },
-		url: new URL('https://example.com'),
-	});
-	expect(data.labels).toBeDefined();
-	expect(data.labels['skipLink.label']).toBe('Aller au contenu');
-});
-
-test('includes localized labels (pt-br)', () => {
-	const route = routes[1]!;
-	const data = generateRouteData({
-		props: { ...route, headings: [{ depth: 1, slug: 'heading-1', text: 'Heading 1' }] },
-		url: new URL('https://example.com'),
-	});
-	expect(data.labels).toBeDefined();
-	expect(data.labels['skipLink.label']).toBe('Pular para o conteúdo');
-});
diff --git a/packages/starlight/__tests__/i18n/translations-fs.test.ts b/packages/starlight/__tests__/i18n/translations-fs.test.ts
index 5b9025aa..0115f1d3 100644
--- a/packages/starlight/__tests__/i18n/translations-fs.test.ts
+++ b/packages/starlight/__tests__/i18n/translations-fs.test.ts
@@ -73,4 +73,32 @@ describe('createTranslationSystemFromFs', () => {
 			)
 		).toThrow(SyntaxError);
 	});
+
+	test('creates a translation system that uses custom strings injected by plugins', () => {
+		const useTranslations = createTranslationSystemFromFs(
+			{
+				locales: { en: { label: 'English', dir: 'ltr' } },
+				defaultLocale: { label: 'English', locale: 'en', dir: 'ltr' },
+			},
+			// Using non-existent `_src/` to ignore custom files in this test fixture.
+			{ srcDir: new URL('./_src/', import.meta.url) },
+			{ en: { 'page.editLink': 'Make this page even more different' } }
+		);
+		const t = useTranslations('en');
+		expect(t('page.editLink')).toMatchInlineSnapshot('"Make this page even more different"');
+	});
+
+	test('creates a translation system that prioritizes user translations over plugin translations', () => {
+		const useTranslations = createTranslationSystemFromFs(
+			{
+				locales: { en: { label: 'English', dir: 'ltr' } },
+				defaultLocale: { label: 'English', locale: 'en', dir: 'ltr' },
+			},
+			// Using `src/` to load custom files in this test fixture.
+			{ srcDir: new URL('./src/', import.meta.url) },
+			{ en: { 'page.editLink': 'Make this page even more different' } }
+		);
+		const t = useTranslations('en');
+		expect(t('page.editLink')).toMatchInlineSnapshot('"Make this page different"');
+	});
 });
diff --git a/packages/starlight/__tests__/i18n/translations.test.ts b/packages/starlight/__tests__/i18n/translations.test.ts
index 35cd9491..e0c0ccbe 100644
--- a/packages/starlight/__tests__/i18n/translations.test.ts
+++ b/packages/starlight/__tests__/i18n/translations.test.ts
@@ -28,3 +28,11 @@ describe('useTranslations()', () => {
 		expect(t('page.nextLink')).not.toBe(translations.en?.['page.nextLink']);
 	});
 });
+
+describe('t.dir()', async () => {
+	test('returns text directions', () => {
+		expect(useTranslations(undefined).dir()).toBe('ltr');
+		expect(useTranslations('fr').dir()).toBe('ltr');
+		expect(useTranslations('ar').dir()).toBe('rtl');
+	});
+});
diff --git a/packages/starlight/__tests__/plugins/translations.test.ts b/packages/starlight/__tests__/plugins/translations.test.ts
new file mode 100644
index 00000000..3f6574f7
--- /dev/null
+++ b/packages/starlight/__tests__/plugins/translations.test.ts
@@ -0,0 +1,48 @@
+import { describe, expect, test, vi } from 'vitest';
+import { useTranslations } from '../../utils/translations';
+
+vi.mock('astro:content', async () =>
+	(await import('../test-utils')).mockedAstroContent({
+		// We do not strip unknown translations in this test so that user-defined translations can
+		// override plugin translations like it would in a real- world scenario were the plugin would
+		// have provided a custom schema to extend the translations.
+		i18n: [['ar', { 'testPlugin3.doThing': 'افعل الشيء' }, { stripUnknown: false }]],
+	})
+);
+
+describe('useTranslations()', () => {
+	test('includes UI strings injected by plugins for the default locale', () => {
+		const t = useTranslations(undefined);
+		expect(t).toBeTypeOf('function');
+		// Include the default locale strings.
+		expect(t('skipLink.label')).toBe('Skip to content');
+		// Include a built-in translation overriden by a plugin.
+		expect(t('search.label')).toBe('Search the thing');
+		// Include a translation injected by a plugin.
+		// @ts-expect-error - translation key injected by a test plugin.
+		expect(t('testPlugin3.doThing')).toBe('Do the Plugin 3 thing');
+	});
+
+	test('includes UI strings injected by plugins', () => {
+		const t = useTranslations('fr');
+		// Include the default locale strings.
+		expect(t('skipLink.label')).toBe('Aller au contenu');
+		// Include a built-in translation overriden by a plugin.
+		expect(t('search.label')).toBe('Rechercher le truc');
+		// Include a translation injected by a plugin.
+		// @ts-expect-error - translation key injected by a test plugin.
+		expect(t('testPlugin3.doThing')).toBe('Faire la chose du plugin 3');
+	});
+
+	test('uses user-defined translations for untranslated strings injected by plugins', () => {
+		const t = useTranslations('pt-br');
+		// @ts-expect-error - translation key injected by a test plugin.
+		expect(t('testPlugin3.doThing')).toBe('Do the Plugin 3 thing');
+	});
+
+	test('prefers user-defined translations over plugin translations', () => {
+		const t = useTranslations('ar');
+		// @ts-expect-error - translation key injected by a test plugin.
+		expect(t('testPlugin3.doThing')).toBe('افعل الشيء');
+	});
+});
diff --git a/packages/starlight/__tests__/plugins/vitest.config.ts b/packages/starlight/__tests__/plugins/vitest.config.ts
index a6eaa3b2..78c4c254 100644
--- a/packages/starlight/__tests__/plugins/vitest.config.ts
+++ b/packages/starlight/__tests__/plugins/vitest.config.ts
@@ -3,6 +3,13 @@ import { defineVitestConfig } from '../test-config';
 export default defineVitestConfig({
 	title: 'Plugins',
 	sidebar: [{ label: 'Getting Started', link: 'getting-started' }],
+	defaultLocale: 'en',
+	locales: {
+		en: { label: 'English', lang: 'en' },
+		fr: { label: 'French' },
+		ar: { label: 'Arabic', dir: 'rtl' },
+		'pt-br': { label: 'Brazilian Portuguese', lang: 'pt-BR' },
+	},
 	plugins: [
 		{
 			name: 'test-plugin-1',
@@ -37,11 +44,24 @@ export default defineVitestConfig({
 		{
 			name: 'test-plugin-3',
 			hooks: {
-				async setup({ config, updateConfig }) {
+				async setup({ config, updateConfig, injectTranslations }) {
 					await Promise.resolve();
 					updateConfig({
 						description: `${config.description} - plugin 3`,
 					});
+					injectTranslations({
+						en: {
+							'search.label': 'Search the thing',
+							'testPlugin3.doThing': 'Do the Plugin 3 thing',
+						},
+						fr: {
+							'search.label': 'Rechercher le truc',
+							'testPlugin3.doThing': 'Faire la chose du plugin 3',
+						},
+						ar: {
+							'testPlugin3.doThing': 'قم بعمل المكون الإضافي 3',
+						},
+					});
 				},
 			},
 		},
diff --git a/packages/starlight/__tests__/test-config.ts b/packages/starlight/__tests__/test-config.ts
index b1a34440..47ab267d 100644
--- a/packages/starlight/__tests__/test-config.ts
+++ b/packages/starlight/__tests__/test-config.ts
@@ -20,15 +20,24 @@ export async function defineVitestConfig(
 	const trailingSlash = opts?.trailingSlash ?? 'ignore';
 	const command = opts?.command ?? 'dev';
 
-	const { starlightConfig } = await runPlugins(config, plugins, createTestPluginContext());
+	const { starlightConfig, pluginTranslations } = await runPlugins(
+		config,
+		plugins,
+		createTestPluginContext()
+	);
 	return getViteConfig({
 		plugins: [
-			vitePluginStarlightUserConfig(command, starlightConfig, {
-				root,
-				srcDir,
-				build,
-				trailingSlash,
-			}),
+			vitePluginStarlightUserConfig(
+				command,
+				starlightConfig,
+				{
+					root,
+					srcDir,
+					build,
+					trailingSlash,
+				},
+				pluginTranslations
+			),
 		],
 		test: {
 			snapshotSerializers: ['./snapshot-serializer-astro-error.ts'],
diff --git a/packages/starlight/__tests__/test-utils.ts b/packages/starlight/__tests__/test-utils.ts
index 2e821544..69b01eda 100644
--- a/packages/starlight/__tests__/test-utils.ts
+++ b/packages/starlight/__tests__/test-utils.ts
@@ -37,8 +37,17 @@ function mockDoc(
 	};
 }
 
-function mockDict(id: string, data: z.input<ReturnType<typeof i18nSchema>>) {
-	return { id, data: i18nSchema().parse(data) };
+function mockDict(
+	id: string,
+	data: z.input<ReturnType<typeof i18nSchema>>,
+	{ stripUnknown } = { stripUnknown: true }
+) {
+	return {
+		id,
+		data: stripUnknown
+			? i18nSchema().parse(data)
+			: i18nSchema().and(z.record(z.string())).parse(data),
+	};
 }
 
 export async function mockedAstroContent({
diff --git a/packages/starlight/components/DraftContentNotice.astro b/packages/starlight/components/DraftContentNotice.astro
index 67cd0466..70d0d4fa 100644
--- a/packages/starlight/components/DraftContentNotice.astro
+++ b/packages/starlight/components/DraftContentNotice.astro
@@ -1,8 +1,6 @@
 ---
 import ContentNotice from './ContentNotice.astro';
 import type { Props } from '../props';
-
-const { labels } = Astro.props;
 ---
 
-<ContentNotice icon="warning" label={labels['page.draft']} />
+<ContentNotice icon="warning" label={Astro.locals.t('page.draft')} />
diff --git a/packages/starlight/components/EditLink.astro b/packages/starlight/components/EditLink.astro
index 74be4c8f..711d3999 100644
--- a/packages/starlight/components/EditLink.astro
+++ b/packages/starlight/components/EditLink.astro
@@ -2,14 +2,14 @@
 import Icon from '../user-components/Icon.astro';
 import type { Props } from '../props';
 
-const { editUrl, labels } = Astro.props;
+const { editUrl } = Astro.props;
 ---
 
 {
 	editUrl && (
 		<a href={editUrl} class="sl-flex">
 			<Icon name="pencil" size="1.2em" />
-			{labels['page.editLink']}
+			{Astro.locals.t('page.editLink')}
 		</a>
 	)
 }
diff --git a/packages/starlight/components/FallbackContentNotice.astro b/packages/starlight/components/FallbackContentNotice.astro
index b3474fb2..616d06fe 100644
--- a/packages/starlight/components/FallbackContentNotice.astro
+++ b/packages/starlight/components/FallbackContentNotice.astro
@@ -1,8 +1,6 @@
 ---
 import ContentNotice from './ContentNotice.astro';
 import type { Props } from '../props';
-
-const { labels } = Astro.props;
 ---
 
-<ContentNotice icon="warning" label={labels['i18n.untranslatedContent']} />
+<ContentNotice icon="warning" label={Astro.locals.t('i18n.untranslatedContent')} />
diff --git a/packages/starlight/components/Footer.astro b/packages/starlight/components/Footer.astro
index f75b5e40..0bba6825 100644
--- a/packages/starlight/components/Footer.astro
+++ b/packages/starlight/components/Footer.astro
@@ -18,7 +18,7 @@ import { Icon } from '../components';
 	{
 		config.credits && (
 			<a class="kudos sl-flex" href="https://starlight.astro.build">
-				<Icon name={'starlight'} /> {Astro.props.labels['builtWithStarlight.label']}
+				<Icon name={'starlight'} /> {Astro.locals.t('builtWithStarlight.label')}
 			</a>
 		)
 	}
diff --git a/packages/starlight/components/LanguageSelect.astro b/packages/starlight/components/LanguageSelect.astro
index c85292dc..42999eac 100644
--- a/packages/starlight/components/LanguageSelect.astro
+++ b/packages/starlight/components/LanguageSelect.astro
@@ -10,8 +10,6 @@ import type { Props } from '../props';
 function localizedPathname(locale: string | undefined): string {
 	return localizedUrl(Astro.url, locale).pathname;
 }
-
-const { labels } = Astro.props;
 ---
 
 {
@@ -19,7 +17,7 @@ const { labels } = Astro.props;
 		<starlight-lang-select>
 			<Select
 				icon="translate"
-				label={labels['languageSelect.accessibleLabel']}
+				label={Astro.locals.t('languageSelect.accessibleLabel')}
 				value={localizedPathname(Astro.props.locale)}
 				options={Object.entries(config.locales).map(([code, locale]) => ({
 					value: localizedPathname(code),
diff --git a/packages/starlight/components/LastUpdated.astro b/packages/starlight/components/LastUpdated.astro
index 6e5fb841..74c28210 100644
--- a/packages/starlight/components/LastUpdated.astro
+++ b/packages/starlight/components/LastUpdated.astro
@@ -1,13 +1,13 @@
 ---
 import type { Props } from '../props';
 
-const { labels, lang, lastUpdated } = Astro.props;
+const { lang, lastUpdated } = Astro.props;
 ---
 
 {
 	lastUpdated && (
 		<p>
-			{labels['page.lastUpdated']}{' '}
+			{Astro.locals.t('page.lastUpdated')}{' '}
 			<time datetime={lastUpdated.toISOString()}>
 				{lastUpdated.toLocaleDateString(lang, { dateStyle: 'medium', timeZone: 'UTC' })}
 			</time>
diff --git a/packages/starlight/components/MobileMenuToggle.astro b/packages/starlight/components/MobileMenuToggle.astro
index b48e1230..56d36e4b 100644
--- a/packages/starlight/components/MobileMenuToggle.astro
+++ b/packages/starlight/components/MobileMenuToggle.astro
@@ -1,14 +1,12 @@
 ---
 import type { Props } from '../props';
 import Icon from '../user-components/Icon.astro';
-
-const { labels } = Astro.props;
 ---
 
 <starlight-menu-button>
 	<button
 		aria-expanded="false"
-		aria-label={labels['menuButton.accessibleLabel']}
+		aria-label={Astro.locals.t('menuButton.accessibleLabel')}
 		aria-controls="starlight__sidebar"
 		class="sl-flex md:sl-hidden"
 	>
diff --git a/packages/starlight/components/MobileTableOfContents.astro b/packages/starlight/components/MobileTableOfContents.astro
index 74342e3c..506ee20b 100644
--- a/packages/starlight/components/MobileTableOfContents.astro
+++ b/packages/starlight/components/MobileTableOfContents.astro
@@ -3,7 +3,7 @@ import Icon from '../user-components/Icon.astro';
 import TableOfContentsList from './TableOfContents/TableOfContentsList.astro';
 import type { Props } from '../props';
 
-const { labels, toc } = Astro.props;
+const { toc } = Astro.props;
 ---
 
 {
@@ -13,7 +13,7 @@ const { labels, toc } = Astro.props;
 				<details id="starlight__mobile-toc">
 					<summary id="starlight__on-this-page--mobile" class="sl-flex">
 						<div class="toggle sl-flex">
-							{labels['tableOfContents.onThisPage']}
+							{Astro.locals.t('tableOfContents.onThisPage')}
 							<Icon name={'right-caret'} class="caret" size="1rem" />
 						</div>
 						<span class="display-current" />
diff --git a/packages/starlight/components/PageFrame.astro b/packages/starlight/components/PageFrame.astro
index 33980343..3a9f0d27 100644
--- a/packages/starlight/components/PageFrame.astro
+++ b/packages/starlight/components/PageFrame.astro
@@ -2,14 +2,14 @@
 import MobileMenuToggle from 'virtual:starlight/components/MobileMenuToggle';
 import type { Props } from '../props';
 
-const { hasSidebar, labels } = Astro.props;
+const { hasSidebar } = Astro.props;
 ---
 
 <div class="page sl-flex">
 	<header class="header"><slot name="header" /></header>
 	{
 		hasSidebar && (
-			<nav class="sidebar" aria-label={labels['sidebarNav.accessibleLabel']}>
+			<nav class="sidebar" aria-label={Astro.locals.t('sidebarNav.accessibleLabel')}>
 				<MobileMenuToggle {...Astro.props} />
 				<div id="starlight__sidebar" class="sidebar-pane">
 					<div class="sidebar-content sl-flex">
diff --git a/packages/starlight/components/Pagination.astro b/packages/starlight/components/Pagination.astro
index 0c92c31e..9ae74521 100644
--- a/packages/starlight/components/Pagination.astro
+++ b/packages/starlight/components/Pagination.astro
@@ -2,7 +2,7 @@
 import Icon from '../user-components/Icon.astro';
 import type { Props } from '../props';
 
-const { dir, labels, pagination } = Astro.props;
+const { dir, pagination } = Astro.props;
 const { prev, next } = pagination;
 const isRtl = dir === 'rtl';
 ---
@@ -13,7 +13,7 @@ const isRtl = dir === 'rtl';
 			<a href={prev.href} rel="prev">
 				<Icon name={isRtl ? 'right-arrow' : 'left-arrow'} size="1.5rem" />
 				<span>
-					{labels['page.previousLink']}
+					{Astro.locals.t('page.previousLink')}
 					<br />
 					<span class="link-title">{prev.label}</span>
 				</span>
@@ -25,7 +25,7 @@ const isRtl = dir === 'rtl';
 			<a href={next.href} rel="next">
 				<Icon name={isRtl ? 'left-arrow' : 'right-arrow'} size="1.5rem" />
 				<span>
-					{labels['page.nextLink']}
+					{Astro.locals.t('page.nextLink')}
 					<br />
 					<span class="link-title">{next.label}</span>
 				</span>
diff --git a/packages/starlight/components/Search.astro b/packages/starlight/components/Search.astro
index 713e9415..c07c6cb6 100644
--- a/packages/starlight/components/Search.astro
+++ b/packages/starlight/components/Search.astro
@@ -4,12 +4,10 @@ import Icon from '../user-components/Icon.astro';
 import project from 'virtual:starlight/project-context';
 import type { Props } from '../props';
 
-const { labels } = Astro.props;
-
 const pagefindTranslations = {
-	placeholder: labels['search.label'],
+	placeholder: Astro.locals.t('search.label'),
 	...Object.fromEntries(
-		Object.entries(labels)
+		Object.entries(Astro.locals.t.all())
 			.filter(([key]) => key.startsWith('pagefind.'))
 			.map(([key, value]) => [key.replace('pagefind.', ''), value])
 	),
@@ -23,28 +21,28 @@ const pagefindTranslations = {
 	<button
 		data-open-modal
 		disabled
-		aria-label={labels['search.label']}
+		aria-label={Astro.locals.t('search.label')}
 		aria-keyshortcuts="Control+K"
 	>
 		<Icon name="magnifier" />
-		<span class="sl-hidden md:sl-block" aria-hidden="true">{labels['search.label']}</span>
+		<span class="sl-hidden md:sl-block" aria-hidden="true">{Astro.locals.t('search.label')}</span>
 		<kbd class="sl-hidden md:sl-flex" style="display: none;">
-			<kbd>{labels['search.ctrlKey']}</kbd><kbd>K</kbd>
+			<kbd>{Astro.locals.t('search.ctrlKey')}</kbd><kbd>K</kbd>
 		</kbd>
 	</button>
 
-	<dialog style="padding:0" aria-label={labels['search.label']}>
+	<dialog style="padding:0" aria-label={Astro.locals.t('search.label')}>
 		<div class="dialog-frame sl-flex">
 			{
 				/* TODO: Make the layout of this button flexible to accommodate different word lengths. Currently hard-coded for English: “Cancel” */
 			}
 			<button data-close-modal class="sl-flex md:sl-hidden">
-				{labels['search.cancelLabel']}
+				{Astro.locals.t('search.cancelLabel')}
 			</button>
 			{
 				import.meta.env.DEV ? (
 					<div style="margin: auto; text-align: center; white-space: pre-line;" dir="ltr">
-						<p>{labels['search.devWarning']}</p>
+						<p>{Astro.locals.t('search.devWarning')}</p>
 					</div>
 				) : (
 					<div class="search-container">
diff --git a/packages/starlight/components/SidebarRestorePoint.astro b/packages/starlight/components/SidebarRestorePoint.astro
index d3d96939..5da9b8b2 100644
--- a/packages/starlight/components/SidebarRestorePoint.astro
+++ b/packages/starlight/components/SidebarRestorePoint.astro
@@ -1,7 +1,7 @@
 ---
 /** Unique symbol for storing a running index in `locals`. */
 const currentGroupIndexSymbol = Symbol.for('starlight-sidebar-group-index');
-const locals = Astro.locals as Record<typeof currentGroupIndexSymbol, number>;
+const locals = Astro.locals as App.Locals & { [currentGroupIndexSymbol]: number };
 
 /** The current sidebar group’s index retrieved from `locals` if set, starting at `0`. */
 const index = locals[currentGroupIndexSymbol] || 0;
diff --git a/packages/starlight/components/SkipLink.astro b/packages/starlight/components/SkipLink.astro
index 307c1ef9..72d18c17 100644
--- a/packages/starlight/components/SkipLink.astro
+++ b/packages/starlight/components/SkipLink.astro
@@ -1,11 +1,9 @@
 ---
 import { PAGE_TITLE_ID } from '../constants';
 import type { Props } from '../props';
-
-const { labels } = Astro.props;
 ---
 
-<a href={`#${PAGE_TITLE_ID}`}>{labels['skipLink.label']}</a>
+<a href={`#${PAGE_TITLE_ID}`}>{Astro.locals.t('skipLink.label')}</a>
 
 <style>
 	a {
diff --git a/packages/starlight/components/TableOfContents.astro b/packages/starlight/components/TableOfContents.astro
index eafd3d86..3d8d9e37 100644
--- a/packages/starlight/components/TableOfContents.astro
+++ b/packages/starlight/components/TableOfContents.astro
@@ -2,14 +2,14 @@
 import TableOfContentsList from './TableOfContents/TableOfContentsList.astro';
 import type { Props } from '../props';
 
-const { labels, toc } = Astro.props;
+const { toc } = Astro.props;
 ---
 
 {
 	toc && (
 		<starlight-toc data-min-h={toc.minHeadingLevel} data-max-h={toc.maxHeadingLevel}>
 			<nav aria-labelledby="starlight__on-this-page">
-				<h2 id="starlight__on-this-page">{labels['tableOfContents.onThisPage']}</h2>
+				<h2 id="starlight__on-this-page">{Astro.locals.t('tableOfContents.onThisPage')}</h2>
 				<TableOfContentsList toc={toc.items} />
 			</nav>
 		</starlight-toc>
diff --git a/packages/starlight/components/ThemeSelect.astro b/packages/starlight/components/ThemeSelect.astro
index 97015602..7db1aff7 100644
--- a/packages/starlight/components/ThemeSelect.astro
+++ b/packages/starlight/components/ThemeSelect.astro
@@ -1,20 +1,18 @@
 ---
 import Select from './Select.astro';
 import type { Props } from '../props';
-
-const { labels } = Astro.props;
 ---
 
 <starlight-theme-select>
 	{/* TODO: Can we give this select a width that works well for each language’s strings? */}
 	<Select
 		icon="laptop"
-		label={labels['themeSelect.accessibleLabel']}
+		label={Astro.locals.t('themeSelect.accessibleLabel')}
 		value="auto"
 		options={[
-			{ label: labels['themeSelect.dark'], selected: false, value: 'dark' },
-			{ label: labels['themeSelect.light'], selected: false, value: 'light' },
-			{ label: labels['themeSelect.auto'], selected: true, value: 'auto' },
+			{ label: Astro.locals.t('themeSelect.dark'), selected: false, value: 'dark' },
+			{ label: Astro.locals.t('themeSelect.light'), selected: false, value: 'light' },
+			{ label: Astro.locals.t('themeSelect.auto'), selected: true, value: 'auto' },
 		]}
 		width="6.25em"
 	/>
diff --git a/packages/starlight/i18n.d.ts b/packages/starlight/i18n.d.ts
new file mode 100644
index 00000000..8cb82217
--- /dev/null
+++ b/packages/starlight/i18n.d.ts
@@ -0,0 +1,18 @@
+/*
+ * This file imports the original `i18next` types and extends them to configure the
+ * Starlight namespace.
+ *
+ * Note that the top-level `import` makes this module non-ambient, so can’t be
+ * combined with other `.d.ts` files such as `locals.d.ts`.
+ */
+
+import 'i18next';
+
+declare module 'i18next' {
+	interface CustomTypeOptions {
+		defaultNS: typeof import('./utils/createTranslationSystem').I18nextNamespace;
+		resources: {
+			starlight: Record<import('./utils/createTranslationSystem').I18nKeys, string>;
+		};
+	}
+}
diff --git a/packages/starlight/index.ts b/packages/starlight/index.ts
index d2a5e572..50b1a87e 100644
--- a/packages/starlight/index.ts
+++ b/packages/starlight/index.ts
@@ -1,3 +1,11 @@
+/**
+ * These triple-slash directives defines dependencies to various declaration files that will be
+ * loaded when a user imports the Starlight integration in their Astro configuration file. These
+ * directives must be first at the top of the file and can only be preceded by this comment.
+ */
+/// <reference path="./locals.d.ts" />
+/// <reference path="./i18n.d.ts" />
+
 import mdx from '@astrojs/mdx';
 import type { AstroIntegration } from 'astro';
 import { spawn } from 'node:child_process';
@@ -9,7 +17,12 @@ import { starlightSitemap } from './integrations/sitemap';
 import { vitePluginStarlightUserConfig } from './integrations/virtual-user-config';
 import { rehypeRtlCodeSupport } from './integrations/code-rtl-support';
 import { createTranslationSystemFromFs } from './utils/translations-fs';
-import { runPlugins, type StarlightUserConfigWithPlugins } from './utils/plugins';
+import {
+	injectPluginTranslationsTypes,
+	runPlugins,
+	type PluginTranslations,
+	type StarlightUserConfigWithPlugins,
+} from './utils/plugins';
 import { processI18nConfig } from './utils/i18n';
 import type { StarlightConfig } from './types';
 
@@ -18,10 +31,12 @@ export default function StarlightIntegration({
 	...opts
 }: StarlightUserConfigWithPlugins): AstroIntegration {
 	let userConfig: StarlightConfig;
+	let pluginTranslations: PluginTranslations = {};
 	return {
 		name: '@astrojs/starlight',
 		hooks: {
 			'astro:config:setup': async ({
+				addMiddleware,
 				command,
 				config,
 				injectRoute,
@@ -42,10 +57,17 @@ export default function StarlightIntegration({
 					config.i18n
 				);
 
-				const { integrations } = pluginResult;
+				const integrations = pluginResult.integrations;
+				pluginTranslations = pluginResult.pluginTranslations;
 				userConfig = starlightConfig;
 
-				const useTranslations = createTranslationSystemFromFs(starlightConfig, config);
+				const useTranslations = createTranslationSystemFromFs(
+					starlightConfig,
+					config,
+					pluginTranslations
+				);
+
+				addMiddleware({ entrypoint: '@astrojs/starlight/locals', order: 'pre' });
 
 				if (!starlightConfig.disable404Route) {
 					injectRoute({
@@ -91,7 +113,9 @@ export default function StarlightIntegration({
 
 				updateConfig({
 					vite: {
-						plugins: [vitePluginStarlightUserConfig(command, starlightConfig, config)],
+						plugins: [
+							vitePluginStarlightUserConfig(command, starlightConfig, config, pluginTranslations),
+						],
 					},
 					markdown: {
 						remarkPlugins: [
@@ -112,6 +136,10 @@ export default function StarlightIntegration({
 				});
 			},
 
+			'astro:config:done': ({ injectTypes }) => {
+				injectPluginTranslationsTypes(pluginTranslations, injectTypes);
+			},
+
 			'astro:build:done': ({ dir }) => {
 				if (!userConfig.pagefind) return;
 				const targetDir = fileURLToPath(dir);
diff --git a/packages/starlight/integrations/asides.ts b/packages/starlight/integrations/asides.ts
index 7c4dfb74..00ca11a6 100644
--- a/packages/starlight/integrations/asides.ts
+++ b/packages/starlight/integrations/asides.ts
@@ -166,7 +166,7 @@ function remarkAsides(options: AsidesOptions): Plugin<[], Root> {
 			// children with the `directiveLabel` property set to true. We want to pass it as the title
 			// prop to <Aside>, so when we find a directive label, we store it for the title prop and
 			// remove the paragraph from the container’s children.
-			let title = t(`aside.${variant}`);
+			let title: string = t(`aside.${variant}`);
 			let titleNode: PhrasingContent[] = [{ type: 'text', value: title }];
 			const firstChild = node.children[0];
 			if (
diff --git a/packages/starlight/integrations/virtual-user-config.ts b/packages/starlight/integrations/virtual-user-config.ts
index 92207e0c..52f60bad 100644
--- a/packages/starlight/integrations/virtual-user-config.ts
+++ b/packages/starlight/integrations/virtual-user-config.ts
@@ -3,6 +3,7 @@ import { resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import type { StarlightConfig } from '../utils/user-config';
 import { getAllNewestCommitDate } from '../utils/git';
+import type { PluginTranslations } from '../utils/plugins';
 
 function resolveVirtualModuleId<T extends string>(id: T): `\0${T}` {
 	return `\0${id}`;
@@ -19,7 +20,8 @@ export function vitePluginStarlightUserConfig(
 		trailingSlash,
 	}: Pick<AstroConfig, 'root' | 'srcDir' | 'trailingSlash'> & {
 		build: Pick<AstroConfig['build'], 'format'>;
-	}
+	},
+	pluginTranslations: PluginTranslations
 ): NonNullable<ViteUserConfig['plugins']>[number] {
 	/**
 	 * Resolves module IDs to a usable format:
@@ -80,6 +82,7 @@ export function vitePluginStarlightUserConfig(
 				userCollections = (await import(${resolveId('./content/config.ts', srcDir)})).collections;
 			} catch {}
 			export const collections = userCollections;`,
+		'virtual:starlight/plugin-translations': `export default ${JSON.stringify(pluginTranslations)}`,
 		...virtualComponentModules,
 	} satisfies Record<string, string>;
 
diff --git a/packages/starlight/locals.d.ts b/packages/starlight/locals.d.ts
new file mode 100644
index 00000000..160b5eae
--- /dev/null
+++ b/packages/starlight/locals.d.ts
@@ -0,0 +1,17 @@
+/**
+ * This namespace is reserved for Starlight (only used for i18n at the moment).
+ * It can be extended by plugins using module augmentation and interface merging.
+ * For an example, see: https://starlight.astro.build/reference/plugins/#injecttranslations
+ */
+declare namespace StarlightApp {
+	interface I18n {}
+}
+
+/**
+ * Extending Astro’s `App.Locals` interface registers types for the middleware added by Starlight.
+ */
+declare namespace App {
+	interface Locals {
+		t: import('./utils/createTranslationSystem').I18nT;
+	}
+}
diff --git a/packages/starlight/locals.ts b/packages/starlight/locals.ts
new file mode 100644
index 00000000..481a8e01
--- /dev/null
+++ b/packages/starlight/locals.ts
@@ -0,0 +1,8 @@
+import { defineMiddleware } from 'astro:middleware';
+import { useTranslations } from './utils/translations';
+
+export const onRequest = defineMiddleware((context, next) => {
+	context.locals.t = useTranslations(context.currentLocale);
+
+	return next();
+});
diff --git a/packages/starlight/package.json b/packages/starlight/package.json
index f1b4c1d0..e154d8e6 100644
--- a/packages/starlight/package.json
+++ b/packages/starlight/package.json
@@ -26,6 +26,7 @@
   "type": "module",
   "exports": {
     ".": "./index.ts",
+    "./locals": "./locals.ts",
     "./components": "./components.ts",
     "./components/LanguageSelect.astro": {
       "types": "./components/LanguageSelect.astro.tsx",
@@ -171,7 +172,7 @@
     "./style/markdown.css": "./style/markdown.css"
   },
   "peerDependencies": {
-    "astro": "^4.8.6"
+    "astro": "^4.14.0"
   },
   "devDependencies": {
     "@astrojs/markdown-remark": "^5.1.0",
@@ -194,6 +195,7 @@
     "hast-util-select": "^6.0.2",
     "hast-util-to-string": "^3.0.0",
     "hastscript": "^9.0.0",
+    "i18next": "^23.11.5",
     "mdast-util-directive": "^3.0.0",
     "mdast-util-to-markdown": "^2.1.0",
     "mdast-util-to-string": "^4.0.0",
diff --git a/packages/starlight/utils/createTranslationSystem.ts b/packages/starlight/utils/createTranslationSystem.ts
index c65c7f6b..8bbd13dc 100644
--- a/packages/starlight/utils/createTranslationSystem.ts
+++ b/packages/starlight/utils/createTranslationSystem.ts
@@ -1,27 +1,60 @@
+import i18next, { type ExistsFunction, type TFunction } from 'i18next';
 import type { i18nSchemaOutput } from '../schemas/i18n';
 import builtinTranslations from '../translations/index';
 import { BuiltInDefaultLocale } from './i18n';
 import type { StarlightConfig } from './user-config';
+import type { UserI18nKeys, UserI18nSchema } from './translations';
+
+/**
+ * The namespace for i18next resources used by Starlight.
+ * All translations handled by Starlight are stored in the same namespace and Starlight always use
+ * a new instance of i18next configured for this namespace.
+ */
+export const I18nextNamespace = 'starlight' as const;
 
 export function createTranslationSystem<T extends i18nSchemaOutput>(
+	config: Pick<StarlightConfig, 'defaultLocale' | 'locales'>,
 	userTranslations: Record<string, T>,
-	config: Pick<StarlightConfig, 'defaultLocale' | 'locales'>
+	pluginTranslations: Record<string, T> = {}
 ) {
-	/** User-configured default locale. */
-	const defaultLocale = config.defaultLocale?.locale || 'root';
+	const defaultLocale =
+		config.defaultLocale.lang || config.defaultLocale?.locale || BuiltInDefaultLocale.lang;
 
-	/** Default map of UI strings based on Starlight and user-configured defaults. */
-	const defaults = buildDictionary(
-		builtinTranslations.en!,
-		userTranslations.en,
-		builtinTranslations[defaultLocale] || builtinTranslations[stripLangRegion(defaultLocale)],
-		userTranslations[defaultLocale]
-	);
+	const translations = {
+		[defaultLocale]: buildResources(
+			builtinTranslations[defaultLocale],
+			builtinTranslations[stripLangRegion(defaultLocale)],
+			pluginTranslations[defaultLocale],
+			userTranslations[defaultLocale]
+		),
+	};
+
+	if (config.locales) {
+		for (const locale in config.locales) {
+			const lang = localeToLang(locale, config.locales, config.defaultLocale);
+
+			translations[lang] = buildResources(
+				builtinTranslations[lang] || builtinTranslations[stripLangRegion(lang)],
+				pluginTranslations[lang],
+				userTranslations[lang]
+			);
+		}
+	}
+
+	const i18n = i18next.createInstance();
+	i18n.init({
+		resources: translations,
+		fallbackLng:
+			config.defaultLocale.lang || config.defaultLocale?.locale || BuiltInDefaultLocale.lang,
+	});
 
 	/**
 	 * Generate a utility function that returns UI strings for the given `locale`.
 	 *
-	 * Also includes an `all()` method for getting the entire dictionary.
+	 * Also includes a few utility methods:
+	 * - `all()` method for getting the entire dictionary.
+	 * - `exists()` method for checking if a key exists in the dictionary.
+	 * - `dir()` method for getting the text direction of the locale.
 	 *
 	 * @param {string | undefined} [locale]
 	 * @example
@@ -30,16 +63,19 @@ export function createTranslationSystem<T extends i18nSchemaOutput>(
 	 * // => 'Search'
 	 * const dictionary = t.all();
 	 * // => { 'skipLink.label': 'Skip to content', 'search.label': 'Search', ... }
+	 * const exists = t.exists('search.label');
+	 * // => true
+	 * const dir = t.dir();
+	 * // => 'ltr'
 	 */
-	return function useTranslations(locale: string | undefined) {
+	return (locale: string | undefined) => {
 		const lang = localeToLang(locale, config.locales, config.defaultLocale);
-		const dictionary = buildDictionary(
-			defaults,
-			builtinTranslations[lang] || builtinTranslations[stripLangRegion(lang)],
-			userTranslations[lang]
-		);
-		const t = <K extends keyof typeof dictionary>(key: K) => dictionary[key];
-		t.all = () => dictionary;
+
+		const t = i18n.getFixedT(lang, I18nextNamespace) as I18nT;
+		t.all = () => i18n.getResourceBundle(lang, I18nextNamespace);
+		t.exists = (key, options) => i18n.exists(key, { lng: lang, ns: I18nextNamespace, ...options });
+		t.dir = (dirLang = lang) => i18n.dir(dirLang);
+
 		return t;
 	};
 }
@@ -70,12 +106,11 @@ function localeToLang(
 
 type BuiltInStrings = (typeof builtinTranslations)['en'];
 
-/** Build a dictionary by layering preferred translation sources. */
-function buildDictionary<T extends Record<string, string | undefined>>(
-	base: BuiltInStrings,
+/** Build an i18next resources dictionary by layering preferred translation sources. */
+function buildResources<T extends Record<string, string | undefined>>(
 	...dictionaries: (T | BuiltInStrings | undefined)[]
-): BuiltInStrings & T {
-	const dictionary = { ...base };
+): { [I18nextNamespace]: BuiltInStrings & T } {
+	const dictionary: Partial<BuiltInStrings> = {};
 	// Iterate over alternate dictionaries to avoid overwriting preceding values with `undefined`.
 	for (const dict of dictionaries) {
 		for (const key in dict) {
@@ -83,5 +118,13 @@ function buildDictionary<T extends Record<string, string | undefined>>(
 			if (value) dictionary[key as keyof typeof dictionary] = value;
 		}
 	}
-	return dictionary as BuiltInStrings & T;
+	return { [I18nextNamespace]: dictionary as BuiltInStrings & T };
 }
+
+export type I18nKeys = UserI18nKeys | keyof StarlightApp.I18n;
+
+export type I18nT = TFunction<'starlight', undefined> & {
+	all: () => UserI18nSchema;
+	exists: ExistsFunction;
+	dir: (lang?: string) => 'ltr' | 'rtl';
+};
diff --git a/packages/starlight/utils/i18n.ts b/packages/starlight/utils/i18n.ts
index 6c9816d0..68d4f84c 100644
--- a/packages/starlight/utils/i18n.ts
+++ b/packages/starlight/utils/i18n.ts
@@ -3,6 +3,26 @@ import { AstroError } from 'astro/errors';
 import type { StarlightConfig } from './user-config';
 
 /**
+ * A proxy object that throws an error when a user tries to access the deprecated `labels` prop in
+ * a component override.
+ *
+ * @todo Remove in a future release once people have updated — no later than v1.
+ */
+export const DeprecatedLabelsPropProxy = new Proxy<Record<string, never>>(
+	{},
+	{
+		get(_, key) {
+			const label = String(key);
+			throw new AstroError(
+				`The \`labels\` prop in component overrides has been removed.`,
+				`Replace \`Astro.props.labels["${label}"]\` with \`Astro.locals.t("${label}")\` instead.\n` +
+					'For more information see https://starlight.astro.build/guides/i18n/#using-ui-translations'
+			);
+		},
+	}
+);
+
+/**
  * A list of well-known right-to-left languages used as a fallback when determining the text
  * direction of a locale is not supported by the `Intl.Locale` API in the current environment.
  *
diff --git a/packages/starlight/utils/plugins.ts b/packages/starlight/utils/plugins.ts
index e0df8ceb..1eaf337e 100644
--- a/packages/starlight/utils/plugins.ts
+++ b/packages/starlight/utils/plugins.ts
@@ -1,8 +1,9 @@
-import type { AstroIntegration } from 'astro';
+import type { AstroIntegration, HookParameters } from 'astro';
 import { z } from 'astro/zod';
 import { StarlightConfigSchema, type StarlightUserConfig } from '../utils/user-config';
 import { parseWithFriendlyErrors } from '../utils/error-map';
 import { AstroError } from 'astro/errors';
+import type { UserI18nSchema } from './translations';
 
 /**
  * Runs Starlight plugins in the order that they are configured after validating the user-provided
@@ -32,6 +33,8 @@ export async function runPlugins(
 
 	// A list of Astro integrations added by the various plugins.
 	const integrations: AstroIntegration[] = [];
+	// A list of translations injected by the various plugins keyed by locale.
+	const pluginTranslations: PluginTranslations = {};
 
 	for (const {
 		name,
@@ -70,6 +73,13 @@ export async function runPlugins(
 			command: context.command,
 			isRestart: context.isRestart,
 			logger: context.logger.fork(name),
+			injectTranslations(translations) {
+				// Merge the translations injected by the plugin.
+				for (const [locale, localeTranslations] of Object.entries(translations)) {
+					pluginTranslations[locale] ??= {};
+					Object.assign(pluginTranslations[locale]!, localeTranslations);
+				}
+			},
 		});
 	}
 
@@ -81,7 +91,34 @@ export async function runPlugins(
 		);
 	}
 
-	return { integrations, starlightConfig };
+	return { integrations, starlightConfig, pluginTranslations };
+}
+
+export function injectPluginTranslationsTypes(
+	translations: PluginTranslations,
+	injectTypes: HookParameters<'astro:config:done'>['injectTypes']
+) {
+	const allKeys = new Set<string>();
+
+	for (const localeTranslations of Object.values(translations)) {
+		for (const key of Object.keys(localeTranslations)) {
+			allKeys.add(key);
+		}
+	}
+
+	// If there are no translations to inject, we don't need to generate any types or cleanup
+	// previous ones as they will not be referenced anymore.
+	if (allKeys.size === 0) return;
+
+	injectTypes({
+		filename: 'i18n-plugins.d.ts',
+		content: `declare namespace StarlightApp {
+	type PluginUIStringKeys = {
+		${[...allKeys].map((key) => `'${key}': string;`).join('\n\t\t')}
+	};
+	interface I18n extends PluginUIStringKeys {}
+}`,
+	});
 }
 
 // https://github.com/withastro/astro/blob/910eb00fe0b70ca80bd09520ae100e8c78b675b5/packages/astro/src/core/config/schema.ts#L113
@@ -192,6 +229,32 @@ const starlightPluginSchema = baseStarlightPluginSchema.extend({
 					 * @see https://docs.astro.build/en/reference/integrations-reference/#astrointegrationlogger
 					 */
 					logger: z.any() as z.Schema<StarlightPluginContext['logger']>,
+					/**
+					 * A callback function to add or update translations strings.
+					 *
+					 * @see https://starlight.astro.build/guides/i18n/#extend-translation-schema
+					 *
+					 * @example
+					 * {
+					 * 	name: 'My Starlight Plugin',
+					 * 	hooks: {
+					 * 		setup({ injectTranslations }) {
+					 * 			injectTranslations({
+					 * 				en: {
+					 * 					'myPlugin.doThing': 'Do the thing',
+					 * 				},
+					 * 				fr: {
+					 * 					'myPlugin.doThing': 'Faire le truc',
+					 * 				},
+					 * 			});
+					 * 		}
+					 * 	}
+					 * }
+					 */
+					injectTranslations: z.function(
+						z.tuple([z.record(z.string(), z.record(z.string(), z.string()))]),
+						z.void()
+					),
 				}),
 			]),
 			z.union([z.void(), z.promise(z.void())])
@@ -222,3 +285,5 @@ export type StarlightPluginContext = Pick<
 	Parameters<NonNullable<AstroIntegration['hooks']['astro:config:setup']>>[0],
 	'command' | 'config' | 'isRestart' | 'logger'
 >;
+
+export type PluginTranslations = Record<string, UserI18nSchema & Record<string, string>>;
diff --git a/packages/starlight/utils/route-data.ts b/packages/starlight/utils/route-data.ts
index 6a3e3a2a..c64571f9 100644
--- a/packages/starlight/utils/route-data.ts
+++ b/packages/starlight/utils/route-data.ts
@@ -7,8 +7,9 @@ import { getPrevNextLinks, getSidebar, type SidebarEntry } from './navigation';
 import { ensureTrailingSlash } from './path';
 import type { Route } from './routing';
 import { localizedId } from './slugs';
-import { useTranslations } from './translations';
 import { formatPath } from './format-path';
+import { useTranslations } from './translations';
+import { DeprecatedLabelsPropProxy } from './i18n';
 
 export interface PageProps extends Route {
 	headings: MarkdownHeading[];
@@ -33,8 +34,8 @@ export interface StarlightRouteData extends Route {
 	lastUpdated: Date | undefined;
 	/** URL object for the address where this page can be edited if enabled. */
 	editUrl: URL | undefined;
-	/** Record of UI strings localized for the current page. */
-	labels: ReturnType<ReturnType<typeof useTranslations>['all']>;
+	/** @deprecated Use `Astro.locals.t()` instead. */
+	labels: Record<string, never>;
 }
 
 export function generateRouteData({
@@ -57,7 +58,7 @@ export function generateRouteData({
 		toc: getToC(props),
 		lastUpdated: getLastUpdated(props),
 		editUrl: getEditUrl(props),
-		labels: useTranslations(locale).all(),
+		labels: DeprecatedLabelsPropProxy,
 	};
 }
 
diff --git a/packages/starlight/utils/starlight-page.ts b/packages/starlight/utils/starlight-page.ts
index b45d088f..a25a000f 100644
--- a/packages/starlight/utils/starlight-page.ts
+++ b/packages/starlight/utils/starlight-page.ts
@@ -13,8 +13,9 @@ import {
 import type { StarlightDocsEntry } from './routing';
 import { slugToLocaleData, urlToSlug } from './slugs';
 import { getPrevNextLinks, getSidebarFromConfig } from './navigation';
-import { useTranslations } from './translations';
 import { docsSchema } from '../schema';
+import type { Prettify, RemoveIndexSignature } from './types';
+import { DeprecatedLabelsPropProxy } from './i18n';
 import { SidebarItemSchema } from '../schemas/sidebar';
 import type { StarlightConfig, StarlightUserConfig } from './user-config';
 
@@ -151,7 +152,7 @@ export async function generateStarlightPageRouteData({
 		entryMeta,
 		hasSidebar: props.hasSidebar ?? entry.data.template !== 'splash',
 		headings,
-		labels: useTranslations(localeData.locale).all(),
+		labels: DeprecatedLabelsPropProxy,
 		lastUpdated,
 		pagination: getPrevNextLinks(sidebar, config.pagination, entry.data),
 		sidebar,
@@ -214,19 +215,3 @@ async function getUserDocsSchema(): Promise<
 	const userCollections = (await import('virtual:starlight/collection-config')).collections;
 	return userCollections?.docs.schema ?? docsSchema();
 }
-
-// https://stackoverflow.com/a/66252656/1945960
-type RemoveIndexSignature<T> = {
-	[K in keyof T as string extends K
-		? never
-		: number extends K
-			? never
-			: symbol extends K
-				? never
-				: K]: T[K];
-};
-
-// https://www.totaltypescript.com/concepts/the-prettify-helper
-type Prettify<T> = {
-	[K in keyof T]: T[K];
-} & {};
diff --git a/packages/starlight/utils/translations-fs.ts b/packages/starlight/utils/translations-fs.ts
index d218f19e..cd927aa5 100644
--- a/packages/starlight/utils/translations-fs.ts
+++ b/packages/starlight/utils/translations-fs.ts
@@ -11,9 +11,10 @@ import type { AstroConfig } from 'astro';
  *
  * @see [`./translations.ts`](./translations.ts)
  */
-export function createTranslationSystemFromFs(
+export function createTranslationSystemFromFs<T extends i18nSchemaOutput>(
 	opts: Pick<StarlightConfig, 'defaultLocale' | 'locales'>,
-	{ srcDir }: Pick<AstroConfig, 'srcDir'>
+	{ srcDir }: Pick<AstroConfig, 'srcDir'>,
+	pluginTranslations: Record<string, T> = {}
 ) {
 	/** All translation data from the i18n collection, keyed by `id`, which matches locale. */
 	let userTranslations: Record<string, i18nSchemaOutput> = {};
@@ -40,5 +41,5 @@ export function createTranslationSystemFromFs(
 		}
 	}
 
-	return createTranslationSystem(userTranslations, opts);
+	return createTranslationSystem(opts, userTranslations, pluginTranslations);
 }
diff --git a/packages/starlight/utils/translations.ts b/packages/starlight/utils/translations.ts
index bbcbc45e..a2dcea44 100644
--- a/packages/starlight/utils/translations.ts
+++ b/packages/starlight/utils/translations.ts
@@ -1,13 +1,16 @@
 import { getCollection, type CollectionEntry, type DataCollectionKey } from 'astro:content';
 import config from 'virtual:starlight/user-config';
+import pluginTranslations from 'virtual:starlight/plugin-translations';
 import type { i18nSchemaOutput } from '../schemas/i18n';
 import { createTranslationSystem } from './createTranslationSystem';
+import type { RemoveIndexSignature } from './types';
 
-type UserI18nSchema = 'i18n' extends DataCollectionKey
+export type UserI18nSchema = 'i18n' extends DataCollectionKey
 	? CollectionEntry<'i18n'> extends { data: infer T }
-		? T
+		? i18nSchemaOutput & T
 		: i18nSchemaOutput
 	: i18nSchemaOutput;
+export type UserI18nKeys = keyof RemoveIndexSignature<UserI18nSchema>;
 
 /** Get all translation data from the i18n collection, keyed by `id`, which matches locale. */
 async function loadTranslations() {
@@ -34,4 +37,8 @@ async function loadTranslations() {
  * const t = useTranslations('en');
  * const label = t('search.label'); // => 'Search'
  */
-export const useTranslations = createTranslationSystem(await loadTranslations(), config);
+export const useTranslations = createTranslationSystem(
+	config,
+	await loadTranslations(),
+	pluginTranslations
+);
diff --git a/packages/starlight/utils/types.ts b/packages/starlight/utils/types.ts
new file mode 100644
index 00000000..7598d6e8
--- /dev/null
+++ b/packages/starlight/utils/types.ts
@@ -0,0 +1,15 @@
+// https://stackoverflow.com/a/66252656/1945960
+export type RemoveIndexSignature<T> = {
+	[K in keyof T as string extends K
+		? never
+		: number extends K
+		? never
+		: symbol extends K
+		? never
+		: K]: T[K];
+};
+
+// https://www.totaltypescript.com/concepts/the-prettify-helper
+export type Prettify<T> = {
+	[K in keyof T]: T[K];
+} & {};
diff --git a/packages/starlight/virtual.d.ts b/packages/starlight/virtual.d.ts
index de3ba265..f7475aa8 100644
--- a/packages/starlight/virtual.d.ts
+++ b/packages/starlight/virtual.d.ts
@@ -28,6 +28,11 @@ declare module 'virtual:starlight/user-images' {
 	};
 }
 
+declare module 'virtual:starlight/plugin-translations' {
+	const PluginTranslations: import('./utils/plugins').PluginTranslations;
+	export default PluginTranslations;
+}
+
 declare module 'virtual:starlight/collection-config' {
 	export const collections: import('astro:content').ContentConfig['collections'] | undefined;
 }
diff --git a/packages/starlight/vitest.config.ts b/packages/starlight/vitest.config.ts
index e15ce187..47ca99be 100644
--- a/packages/starlight/vitest.config.ts
+++ b/packages/starlight/vitest.config.ts
@@ -21,10 +21,10 @@ export default defineConfig({
 			],
 			thresholds: {
 				autoUpdate: true,
-				lines: 89.53,
-				functions: 94.08,
-				branches: 93.07,
-				statements: 89.53,
+				lines: 89.18,
+				functions: 92.7,
+				branches: 93.04,
+				statements: 89.18,
 			},
 		},
 	},
diff --git a/packages/tailwind/package.json b/packages/tailwind/package.json
index f5638d3c..2787840b 100644
--- a/packages/tailwind/package.json
+++ b/packages/tailwind/package.json
@@ -25,6 +25,7 @@
   "devDependencies": {
     "@vitest/coverage-v8": "^1.6.0",
     "postcss": "^8.4.38",
+    "tailwindcss": "^3.3.3",
     "vitest": "^1.6.0"
   },
   "peerDependencies": {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index ac9b53a9..5233b638 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -1,7 +1,7 @@
 lockfileVersion: '6.0'
 
 settings:
-  autoInstallPeers: true
+  autoInstallPeers: false
   excludeLinksFromLockfile: false
 
 importers:
@@ -123,15 +123,16 @@ importers:
 
   packages/docsearch:
     dependencies:
-      '@astrojs/starlight':
-        specifier: '>=0.14.0'
-        version: link:../starlight
       '@docsearch/css':
         specifier: ^3.6.0
         version: 3.6.0
       '@docsearch/js':
         specifier: ^3.6.0
-        version: 3.6.0(@algolia/client-search@4.20.0)(search-insights@2.11.0)
+        version: 3.6.0
+    devDependencies:
+      '@astrojs/starlight':
+        specifier: workspace:*
+        version: link:../starlight
 
   packages/file-icons-generator:
     dependencies:
@@ -147,14 +148,13 @@ importers:
         version: 1.3.8
 
   packages/markdoc:
-    dependencies:
+    devDependencies:
       '@astrojs/markdoc':
         specifier: ^0.11.4
         version: 0.11.4(astro@4.15.3)
       '@astrojs/starlight':
-        specifier: '>=0.23.0'
+        specifier: workspace:*
         version: link:../starlight
-    devDependencies:
       vitest:
         specifier: ^1.6.0
         version: 1.6.0(@types/node@18.16.19)
@@ -194,6 +194,9 @@ importers:
       hastscript:
         specifier: ^9.0.0
         version: 9.0.0
+      i18next:
+        specifier: ^23.11.5
+        version: 23.11.5
       mdast-util-directive:
         specifier: ^3.0.0
         version: 3.0.0
@@ -287,16 +290,6 @@ importers:
         version: 4.15.3(@types/node@18.16.19)(typescript@5.4.5)
 
   packages/tailwind:
-    dependencies:
-      '@astrojs/starlight':
-        specifier: '>=0.9.0'
-        version: link:../starlight
-      '@astrojs/tailwind':
-        specifier: ^5.0.0
-        version: 5.1.0(astro@4.15.3)(tailwindcss@3.4.4)
-      tailwindcss:
-        specifier: ^3.3.3
-        version: 3.4.4
     devDependencies:
       '@vitest/coverage-v8':
         specifier: ^1.6.0
@@ -304,53 +297,62 @@ importers:
       postcss:
         specifier: ^8.4.38
         version: 8.4.45
+      tailwindcss:
+        specifier: ^3.3.3
+        version: 3.4.4
       vitest:
         specifier: ^1.6.0
         version: 1.6.0(@types/node@18.16.19)
 
 packages:
 
-  /@algolia/autocomplete-core@1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)(search-insights@2.11.0):
+  /@algolia/autocomplete-core@1.9.3(algoliasearch@4.20.0):
     resolution: {integrity: sha512-009HdfugtGCdC4JdXUbVJClA0q0zh24yyePn+KUGk3rP7j8FEe/m5Yo/z65gn6nP/cM39PxpzqKrL7A6fP6PPw==}
     dependencies:
-      '@algolia/autocomplete-plugin-algolia-insights': 1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)(search-insights@2.11.0)
-      '@algolia/autocomplete-shared': 1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)
+      '@algolia/autocomplete-plugin-algolia-insights': 1.9.3(algoliasearch@4.20.0)
+      '@algolia/autocomplete-shared': 1.9.3(algoliasearch@4.20.0)
     transitivePeerDependencies:
       - '@algolia/client-search'
       - algoliasearch
       - search-insights
     dev: false
 
-  /@algolia/autocomplete-plugin-algolia-insights@1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)(search-insights@2.11.0):
+  /@algolia/autocomplete-plugin-algolia-insights@1.9.3(algoliasearch@4.20.0):
     resolution: {integrity: sha512-a/yTUkcO/Vyy+JffmAnTWbr4/90cLzw+CC3bRbhnULr/EM0fGNvM13oQQ14f2moLMcVDyAx/leczLlAOovhSZg==}
     peerDependencies:
       search-insights: '>= 1 < 3'
+    peerDependenciesMeta:
+      search-insights:
+        optional: true
     dependencies:
-      '@algolia/autocomplete-shared': 1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)
-      search-insights: 2.11.0
+      '@algolia/autocomplete-shared': 1.9.3(algoliasearch@4.20.0)
     transitivePeerDependencies:
       - '@algolia/client-search'
       - algoliasearch
     dev: false
 
-  /@algolia/autocomplete-preset-algolia@1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0):
+  /@algolia/autocomplete-preset-algolia@1.9.3(algoliasearch@4.20.0):
     resolution: {integrity: sha512-d4qlt6YmrLMYy95n5TB52wtNDr6EgAIPH81dvvvW8UmuWRgxEtY0NJiPwl/h95JtG2vmRM804M0DSwMCNZlzRA==}
     peerDependencies:
       '@algolia/client-search': '>= 4.9.1 < 6'
       algoliasearch: '>= 4.9.1 < 6'
+    peerDependenciesMeta:
+      '@algolia/client-search':
+        optional: true
     dependencies:
-      '@algolia/autocomplete-shared': 1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)
-      '@algolia/client-search': 4.20.0
+      '@algolia/autocomplete-shared': 1.9.3(algoliasearch@4.20.0)
       algoliasearch: 4.20.0
     dev: false
 
-  /@algolia/autocomplete-shared@1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0):
+  /@algolia/autocomplete-shared@1.9.3(algoliasearch@4.20.0):
     resolution: {integrity: sha512-Wnm9E4Ye6Rl6sTTqjoymD+l8DjSTHsHboVRYrKgEt8Q7UHm9nYbqhN/i0fhUYA3OAEH7WA8x3jfpnmJm3rKvaQ==}
     peerDependencies:
       '@algolia/client-search': '>= 4.9.1 < 6'
       algoliasearch: '>= 4.9.1 < 6'
+    peerDependenciesMeta:
+      '@algolia/client-search':
+        optional: true
     dependencies:
-      '@algolia/client-search': 4.20.0
       algoliasearch: 4.20.0
     dev: false
 
@@ -447,7 +449,6 @@ packages:
   /@alloc/quick-lru@5.2.0:
     resolution: {integrity: sha512-UrcABB+4bUrFABwbluTIBErXwvbsU/V7TZWfmbgJfbkwiBuziS9gxdODUyuiecfdGQ85jglMW6juS3+z5TsKLw==}
     engines: {node: '>=10'}
-    dev: false
 
   /@ampproject/remapping@2.2.1:
     resolution: {integrity: sha512-lFMjJTrFL3j7L9yBxwYfCq2k6qqwHyzuUl/XBnif78PWTJYyL/dfowQHWE3sp6U6ZzqWiiIZnpTMO96zhkjwtg==}
@@ -545,7 +546,6 @@ packages:
       - '@types/react'
       - react
       - supports-color
-    dev: false
 
   /@astrojs/markdown-remark@5.2.0:
     resolution: {integrity: sha512-vWGM24KZXz11jR3JO+oqYU3T2qpuOi4uGivJ9SQLCAI01+vEkHC60YJMRvHPc+hwd60F7euNs1PeOEixIIiNQw==}
@@ -812,6 +812,13 @@ packages:
       regenerator-runtime: 0.13.11
     dev: true
 
+  /@babel/runtime@7.24.7:
+    resolution: {integrity: sha512-UwgBRMjJP+xv857DCngvqXI3Iq6J4v0wXmwc6sapg+zyhbwmQX67LUEFrkK5tbyJ30jGuG3ZvWpBiB9LCy1kWw==}
+    engines: {node: '>=6.9.0'}
+    dependencies:
+      regenerator-runtime: 0.14.1
+    dev: false
+
   /@babel/template@7.25.0:
     resolution: {integrity: sha512-aOOgh1/5XzKvg1jvVz7AVrx2piJ2XBi227DHmbY6y+bM9H2FlN+IfecYu4Xl0cNiiVejlsCri89LUsbj8vJD9Q==}
     engines: {node: '>=6.9.0'}
@@ -1075,10 +1082,10 @@ packages:
     resolution: {integrity: sha512-+sbxb71sWre+PwDK7X2T8+bhS6clcVMLwBPznX45Qu6opJcgRjAp7gYSDzVFp187J+feSj5dNBN1mJoi6ckkUQ==}
     dev: false
 
-  /@docsearch/js@3.6.0(@algolia/client-search@4.20.0)(search-insights@2.11.0):
+  /@docsearch/js@3.6.0:
     resolution: {integrity: sha512-QujhqINEElrkIfKwyyyTfbsfMAYCkylInLYMRqHy7PHc8xTBQCow73tlo/Kc7oIwBrCLf0P3YhjlOeV4v8hevQ==}
     dependencies:
-      '@docsearch/react': 3.6.0(@algolia/client-search@4.20.0)(search-insights@2.11.0)
+      '@docsearch/react': 3.6.0
       preact: 10.18.2
     transitivePeerDependencies:
       - '@algolia/client-search'
@@ -1088,7 +1095,7 @@ packages:
       - search-insights
     dev: false
 
-  /@docsearch/react@3.6.0(@algolia/client-search@4.20.0)(search-insights@2.11.0):
+  /@docsearch/react@3.6.0:
     resolution: {integrity: sha512-HUFut4ztcVNmqy9gp/wxNbC7pTOHhgVVkHVGCACTuLhUKUhKAF9KYHJtMiLUJxEqiFLQiuri1fWF8zqwM/cu1w==}
     peerDependencies:
       '@types/react': '>= 16.8.0 < 19.0.0'
@@ -1105,11 +1112,10 @@ packages:
       search-insights:
         optional: true
     dependencies:
-      '@algolia/autocomplete-core': 1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)(search-insights@2.11.0)
-      '@algolia/autocomplete-preset-algolia': 1.9.3(@algolia/client-search@4.20.0)(algoliasearch@4.20.0)
+      '@algolia/autocomplete-core': 1.9.3(algoliasearch@4.20.0)
+      '@algolia/autocomplete-preset-algolia': 1.9.3(algoliasearch@4.20.0)
       '@docsearch/css': 3.6.0
       algoliasearch: 4.20.0
-      search-insights: 2.11.0
     transitivePeerDependencies:
       - '@algolia/client-search'
     dev: false
@@ -1664,7 +1670,6 @@ packages:
         optional: true
     optionalDependencies:
       '@types/markdown-it': 12.2.3
-    dev: false
 
   /@mdx-js/mdx@3.0.1:
     resolution: {integrity: sha512-eIQ4QTrOWyL3LWEe/bu6Taqzq2HQvHcyTMaOrI95P2/LmJE7AsfPfgJGuFLPVqBUE1BC1rik3VIhU+s9u72arA==}
@@ -1995,7 +2000,6 @@ packages:
   /@types/linkify-it@5.0.0:
     resolution: {integrity: sha512-sVDA58zAw4eWAffKOaQH5/5j3XeayukzDk+ewSsnv3p4yJEZHCCzMDiZM8e0OUrRvmpGZ85jf4yDHkHsgBNr9Q==}
     requiresBuild: true
-    dev: false
     optional: true
 
   /@types/markdown-it@12.2.3:
@@ -2004,7 +2008,6 @@ packages:
     dependencies:
       '@types/linkify-it': 5.0.0
       '@types/mdurl': 2.0.0
-    dev: false
     optional: true
 
   /@types/mdast@4.0.4:
@@ -2015,7 +2018,6 @@ packages:
   /@types/mdurl@2.0.0:
     resolution: {integrity: sha512-RGdgjQUZba5p6QEFAVx2OGb8rQDL/cPRG7GiedRzMcJ1tYnUANBncjbSB1NRGwbvjcPeikRABz2nshyPk1bhWg==}
     requiresBuild: true
-    dev: false
     optional: true
 
   /@types/mdx@2.0.5:
@@ -2318,7 +2320,6 @@ packages:
 
   /any-promise@1.3.0:
     resolution: {integrity: sha512-7UvmKalWRt1wgjL1RrGxoSJW/0QZFIegpeGvZG9kjp8vrRu55XTHbwnqq2GpXm9uLbcuhxm3IqX9OB4MZR1b2A==}
-    dev: false
 
   /anymatch@3.1.3:
     resolution: {integrity: sha512-KMReFUr0B4t+D+OBkjR3KYqvocp2XaSzO55UcB6mgQMd3KbcE+mWTyvVV7D/zsdEbNnV6acZUutkiHQXvTr1Rw==}
@@ -2673,7 +2674,6 @@ packages:
   /camelcase-css@2.0.1:
     resolution: {integrity: sha512-QOSvevhslijgYwRx6Rv7zKdMF8lbRmx+uQGx2+vDc+KI/eBnsy9kit5aj23AgGu3pa4t9AgwbnXWqS+iOY+2aA==}
     engines: {node: '>= 6'}
-    dev: false
 
   /camelcase-keys@6.2.2:
     resolution: {integrity: sha512-YrwaA0vEKazPBkn0ipTiMpSajYDSe+KjQfrjhcBMxJt/znbvlHd8Pw/Vamaz5EB4Wfhs3SUR3Z9mwRu/P3s3Yg==}
@@ -2901,7 +2901,6 @@ packages:
   /commander@4.1.1:
     resolution: {integrity: sha512-NOKm8xhkzAjzFx8B2v5OAHT+u5pRQc2UCa2Vq9jYL/31o2wi9mxBA7LIFs3sV5VSC49z6pEhfbMULvShKj26WA==}
     engines: {node: '>= 6'}
-    dev: false
 
   /commander@6.2.1:
     resolution: {integrity: sha512-U7VdrJFnJgo4xjrHpTzu0yrHPGImdsmD95ZlgYSEajAn2JKzDhDTPG9kBTefmObL2w/ngeZnilk+OV9CG3d7UA==}
@@ -3136,7 +3135,6 @@ packages:
 
   /didyoumean@1.2.2:
     resolution: {integrity: sha512-gxtyfqMg7GKyhQmb056K7M3xszy/myH8w+B4RT+QXBQsvAOdc3XymqDDPHx1BgPgsdAA5SIifona89YtRATDzw==}
-    dev: false
 
   /diff-sequences@29.6.3:
     resolution: {integrity: sha512-EjePK1srD3P08o2j4f0ExnylqRs5B9tJjcp9t1krH2qRi8CCdsYfwe9JgSLurFBWwq4uOlipzfk5fHNvwFKr8Q==}
@@ -3757,7 +3755,6 @@ packages:
     engines: {node: '>=10.13.0'}
     dependencies:
       is-glob: 4.0.3
-    dev: false
 
   /glob@7.1.6:
     resolution: {integrity: sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==}
@@ -3769,7 +3766,6 @@ packages:
       minimatch: 3.1.2
       once: 1.4.0
       path-is-absolute: 1.0.1
-    dev: false
 
   /glob@7.2.3:
     resolution: {integrity: sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==}
@@ -4204,6 +4200,12 @@ packages:
     engines: {node: '>=16.17.0'}
     dev: true
 
+  /i18next@23.11.5:
+    resolution: {integrity: sha512-41pvpVbW9rhZPk5xjCX2TPJi2861LEig/YRhUkY+1FQ2IQPS0bKUDYnEqY8XPPbB48h1uIwLnP9iiEfuSl20CA==}
+    dependencies:
+      '@babel/runtime': 7.24.7
+    dev: false
+
   /iconv-lite@0.4.24:
     resolution: {integrity: sha512-v3MXnZAcvnywkTUEZomIActle7RXXeedOR31wwl7VlyoXO4Qi9arvSenNQWne1TcRwhCL1HwLI21bEqdpj8/rA==}
     engines: {node: '>=0.10.0'}
@@ -4603,7 +4605,6 @@ packages:
   /lilconfig@2.1.0:
     resolution: {integrity: sha512-utWOt/GHzuUxnLKxB6dk81RoOeoNeHgbrXiuGk4yyF5qlRz+iIVWu56E2fqGHFrXz0QNUhLB/8nKqvRH66JKGQ==}
     engines: {node: '>=10'}
-    dev: false
 
   /lilconfig@3.1.2:
     resolution: {integrity: sha512-eop+wDAvpItUys0FWkHIKeC9ybYrTGbU41U5K7+bttZZeohvnY7M9dZ5kB21GNWiFT2q1OoPTvncPCgSOVO5ow==}
@@ -5400,7 +5401,6 @@ packages:
       any-promise: 1.3.0
       object-assign: 4.1.1
       thenify-all: 1.6.0
-    dev: false
 
   /nanoid@3.3.7:
     resolution: {integrity: sha512-eSRppjcPIatRIMC1U6UngP8XFcz8MQWGQdt1MTBQ7NaAmvXDfvNxbvWV3x2y6CdEUciCSsDHDQZbhYaB8QEo2g==}
@@ -5515,7 +5515,6 @@ packages:
   /object-hash@3.0.0:
     resolution: {integrity: sha512-RSn9F68PjH9HqtltsSnqYC1XXoWe9Bju5+213R98cNGttag9q9yAOTzdbsqvIa7aNm5WffBZFpWYr2aWrklWAw==}
     engines: {node: '>= 6'}
-    dev: false
 
   /object-inspect@1.12.3:
     resolution: {integrity: sha512-geUvdk7c+eizMNUDkRpW1wJwgfOiOeHbxBR/hLXK1aT6zmVSO0jsQcs7fj6MGw89jC/cjGfLcNOrtMYtGqm81g==}
@@ -5872,7 +5871,6 @@ packages:
   /pirates@4.0.6:
     resolution: {integrity: sha512-saLsH7WeYYPiD25LDuLRRY/i+6HaPYr6G1OUlN39otzkSTxKnubR9RTxS3/Kk50s1g2JTgFwWQDQyplC5/SHZg==}
     engines: {node: '>= 6'}
-    dev: false
 
   /pkg-dir@4.2.0:
     resolution: {integrity: sha512-HRDzbaKjC+AOWVXxAU/x54COGeIv9eb+6CkDSQoNTt4XyWoIJvuPsXizxu/Fr23EiekbtZwmh1IcIG/l/a10GQ==}
@@ -5914,7 +5912,6 @@ packages:
       postcss-value-parser: 4.2.0
       read-cache: 1.0.0
       resolve: 1.22.8
-    dev: false
 
   /postcss-js@4.0.1(postcss@8.4.45):
     resolution: {integrity: sha512-dDLF8pEO191hJMtlHFPRa8xsizHaM82MLfNkUHdUtVEV3tgTp5oj+8qbEqYM57SLfc74KSbw//4SeJma2LRVIw==}
@@ -5924,7 +5921,6 @@ packages:
     dependencies:
       camelcase-css: 2.0.1
       postcss: 8.4.45
-    dev: false
 
   /postcss-load-config@4.0.2(postcss@8.4.45):
     resolution: {integrity: sha512-bSVhyJGL00wMVoPUzAVAnbEoWyqRxkjv64tUl427SKnPrENtq6hJwUojroMz2VB+Q1edmi4IfrAPpami5VVgMQ==}
@@ -5941,7 +5937,6 @@ packages:
       lilconfig: 3.1.2
       postcss: 8.4.45
       yaml: 2.3.4
-    dev: false
 
   /postcss-nested@6.0.1(postcss@8.4.45):
     resolution: {integrity: sha512-mEp4xPMi5bSWiMbsgoPfcP74lsWLHkQbZc3sY+jWYd65CUwXrUaTp0fmNpa01ZcETKlIgUdFN/MpS2xZtqL9dQ==}
@@ -5951,7 +5946,6 @@ packages:
     dependencies:
       postcss: 8.4.45
       postcss-selector-parser: 6.0.13
-    dev: false
 
   /postcss-selector-parser@6.0.13:
     resolution: {integrity: sha512-EaV1Gl4mUEV4ddhDnv/xtj7sxwrwxdetHdWUGnT4VJQf+4d05v6lHYZr8N573k5Z0BViss7BDhfWtKS3+sfAqQ==}
@@ -5959,11 +5953,9 @@ packages:
     dependencies:
       cssesc: 3.0.0
       util-deprecate: 1.0.2
-    dev: false
 
   /postcss-value-parser@4.2.0:
     resolution: {integrity: sha512-1NNCs6uurfkVbeXG4S8JFT9t19m45ICnif8zWLd5oPSZ50QnwMfK+H3jv408d4jw/7Bttv5axS5IiHoLaVNHeQ==}
-    dev: false
 
   /postcss@8.4.45:
     resolution: {integrity: sha512-7KTLTdzdZZYscUc65XmjFiB73vBhBfbPztCYdUNvlaso9PrzjzcmjqBPR0lNGkcVlcO4BjiO5rK/qNz+XAen1Q==}
@@ -6158,7 +6150,6 @@ packages:
     resolution: {integrity: sha512-Owdv/Ft7IjOgm/i0xvNDZ1LrRANRfew4b2prF3OWMQLxLfu3bS8FVhCsrSCMK4lR56Y9ya+AThoTpDCTxCmpRA==}
     dependencies:
       pify: 2.3.0
-    dev: false
 
   /read-pkg-up@7.0.1:
     resolution: {integrity: sha512-zK0TB7Xd6JpCLmlLmufqykGE+/TlOePD6qKClNW7hHDKFh/J7/7gCWGR7joEQEW1bKq3a3yUZSObOoWLFQ4ohg==}
@@ -6215,6 +6206,10 @@ packages:
     resolution: {integrity: sha512-kY1AZVr2Ra+t+piVaJ4gxaFaReZVH40AKNo7UCX6W+dEwBo/2oZJzqfuN1qLq1oL45o56cPaTXELwrTh8Fpggg==}
     dev: true
 
+  /regenerator-runtime@0.14.1:
+    resolution: {integrity: sha512-dYnhHh0nJoMfnkZs6GmmhFknAGRrLznOu5nc9ML+EJxGvrx6H7teuevqVqCuPcPK//3eDrrjQhehXVx9cnkGdw==}
+    dev: false
+
   /regexp.prototype.flags@1.5.0:
     resolution: {integrity: sha512-0SutC3pNudRKgquxGoRGIz946MZVHqbNfPjBdxeOhBrdgDKlRoXmYLQN9xRbrR09ZXWeGAdPuif7egofn6v5LA==}
     engines: {node: '>= 0.4'}
@@ -6492,10 +6487,6 @@ packages:
     resolution: {integrity: sha512-NqVDv9TpANUjFm0N8uM5GxL36UgKi9/atZw+x7YFnQ8ckwFGKrl4xX4yWtrey3UJm5nP1kUbnYgLopqWNSRhWw==}
     dev: false
 
-  /search-insights@2.11.0:
-    resolution: {integrity: sha512-Uin2J8Bpm3xaZi9Y8QibSys6uJOFZ+REMrf42v20AA3FUDUrshKkMEP6liJbMAHCm71wO6ls4mwAf7a3gFVxLw==}
-    dev: false
-
   /section-matter@1.0.0:
     resolution: {integrity: sha512-vfD3pmTzGpufjScBh50YHKzEu2lxBWhVEHsNGoEXmCmn2hKGfeNLYMzCJpe8cD7gqX7TJluOVpBkAequ6dgMmA==}
     engines: {node: '>=4'}
@@ -6994,7 +6985,6 @@ packages:
       mz: 2.7.0
       pirates: 4.0.6
       ts-interface-checker: 0.1.13
-    dev: false
 
   /suf-log@2.5.3:
     resolution: {integrity: sha512-KvC8OPjzdNOe+xQ4XWJV2whQA0aM1kGVczMQ8+dStAO6KfEB140JEVQ9dE76ONZ0/Ylf67ni4tILPJB41U0eow==}
@@ -7048,7 +7038,6 @@ packages:
       sucrase: 3.34.0
     transitivePeerDependencies:
       - ts-node
-    dev: false
 
   /tar-fs@2.1.1:
     resolution: {integrity: sha512-V0r2Y9scmbDRLCNex/+hYzvp/zyYjvFbHPNgVTKfQvVrb6guiE/fxP+XblDNR011utopbkex2nM4dHNV6GDsng==}
@@ -7103,13 +7092,11 @@ packages:
     engines: {node: '>=0.8'}
     dependencies:
       thenify: 3.3.1
-    dev: false
 
   /thenify@3.3.1:
     resolution: {integrity: sha512-RVZSIV5IG10Hk3enotrhvz0T9em6cyHBLkH/YAZuKqd8hRkKhSfCGIcP2KUY0EPxndzANBmNllzWPwak+bheSw==}
     dependencies:
       any-promise: 1.3.0
-    dev: false
 
   /through@2.3.8:
     resolution: {integrity: sha512-w89qg7PI8wAdvX60bMDP+bFoD5Dvhm9oLheFp5O4a2QF0cSBGsBX4qZmadPMvVqlLJBBci+WqGGOAPvcDeNSVg==}
@@ -7179,7 +7166,6 @@ packages:
 
   /ts-interface-checker@0.1.13:
     resolution: {integrity: sha512-Y/arvbn+rrz3JCKl9C4kVNfTfSm2/mEp5FSz5EsZSANGPSlQrpRI5M4PKF+mJnE52jOO90PnPSc3Ur3bTQw0gA==}
-    dev: false
 
   /tsconfck@3.1.3(typescript@5.4.5):
     resolution: {integrity: sha512-ulNZP1SVpRDesxeMLON/LtWM8HIgAJEIVpVVhBM6gsmvQ8+Rh+ZG7FWGvHh7Ah3pRABwVJWklWCr/BTZSv0xnQ==}
@@ -7867,7 +7853,6 @@ packages:
   /yaml@2.3.4:
     resolution: {integrity: sha512-8aAvwVUSHpfEqTQ4w/KMlf3HcRdt50E5ODIQJBw1fQ5RL34xabzxtUlzTXVqc4rkZsPbvrXKWnABCD7kWSmocA==}
     engines: {node: '>= 14'}
-    dev: false
 
   /yargs-parser@18.1.3:
     resolution: {integrity: sha512-o50j0JeToy/4K6OZcaQmW6lyXXKhq7csREXcDwk2omFPJEwUNOVtJKvmDr9EI1fAJZUyZcRF7kxGBWmRXudrCQ==}
diff --git a/tsconfig.json b/tsconfig.json
index f3dbc75e..38ec1b74 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -3,7 +3,6 @@
   "exclude": ["**/dist/**", "**/__coverage__/**"],
   "compilerOptions": {
     "jsx": "preserve",
-    "allowJs": true,
     "checkJs": true
   }
 }