withastro · HiDeoo · Dec 15, 2025 · Dec 17, 2025 · Dec 17, 2025 · Dec 17, 2025
diff --git a/.devcontainer/Dockerfile b/.devcontainer/Dockerfile
@@ -1,5 +1,5 @@
 # Based on https://github.com/withastro/astro/blob/main/.devcontainer/Dockerfile
-FROM mcr.microsoft.com/devcontainers/javascript-node:0-18
+FROM mcr.microsoft.com/devcontainers/javascript-node:0-22
 
 # We uninstall pnpm here, since we enable the corepack version in the postCreateCommand
 # This ensures we respect the "packageManager" version in package.json

diff --git a/.github/ISSUE_TEMPLATE/---01-bug-report.yml b/.github/ISSUE_TEMPLATE/---01-bug-report.yml
@@ -9,7 +9,7 @@ body:
         Thank you for taking the time to file a bug report! Please fill out this form as completely as possible.
 
         ✅ I am using the **latest versions of Starlight and Astro**.
-        ✅ I am using a version of Node that supports ESM (`v14.18.0+`, or `v16.12.0+`).
+        ✅ I am using a compatible version of Node.js (`v22.12.0+`).
   - type: input
     id: starlight-version
     attributes:

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -13,7 +13,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  NODE_VERSION: 18
+  NODE_VERSION: 22
   ASTRO_TELEMETRY_DISABLED: true
 
 jobs:
@@ -69,9 +69,6 @@ jobs:
       - run: pnpm i
       - name: Test packages
         run: pnpm -r test:coverage
-      - name: Test legacy collections support
-        working-directory: packages/starlight
-        run: pnpm test:legacy
 
   e2e-test:
     name: 'Run E2E tests (${{ matrix.os }})'

diff --git a/.github/workflows/file-icons.yml b/.github/workflows/file-icons.yml
@@ -24,7 +24,7 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
         with:
-          node-version: 18.20.8
+          node-version: 22.12.0
           cache: 'pnpm'
 
       - name: Install Dependencies

diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
@@ -18,7 +18,7 @@ jobs:
       - uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4.2.0
       - uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
         with:
-          node-version: 18.20.8
+          node-version: 22.12.0
           cache: 'pnpm'
       - run: pnpm i
       - name: Format with Prettier

diff --git a/.github/workflows/lunaria.yml b/.github/workflows/lunaria.yml
@@ -32,7 +32,7 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
         with:
-          node-version: 20.19.4
+          node-version: 22.12.0
           cache: pnpm
 
       - name: Install dependencies

diff --git a/.github/workflows/size-limit.yml b/.github/workflows/size-limit.yml
@@ -9,6 +9,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.event_name == 'pull_request_target' && github.head_ref || github.ref }}
   cancel-in-progress: true
 
+env:
+  NODE_VERSION: 22
+
 jobs:
   # This basic check runs size-limit for the current branch.
   # It will fail if the branch pushes the size over the specified budget.
@@ -19,6 +22,11 @@ jobs:
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4.2.0
+      - name: Setup Node
+        uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+          cache: 'pnpm'
       - run: pnpm i
       - run: 'pnpm build:examples'
       - run: pnpm size
@@ -32,6 +40,11 @@ jobs:
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4.2.0
+      - name: Setup Node
+        uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+          cache: 'pnpm'
       - name: Run size-limit
         uses: andresz1/size-limit-action@94bc357df29c36c8f8d50ea497c3e225c3c95d1d # v1.8.0
         with:

diff --git a/docs/__a11y__/test-utils.ts b/docs/__a11y__/test-utils.ts
@@ -9,7 +9,7 @@ import Sitemapper from 'sitemapper';
 
 // We use the Lunaria config to get the list of languages rather than the Astro config as importing
 // the latter does not play well with Playwright.
-import lunariaConfig from '../lunaria.config.json' assert { type: 'json' };
+import lunariaConfig from '../lunaria.config.json' with { type: 'json' };
 
 export { expect, type Locator } from '@playwright/test';
 
@@ -72,7 +72,11 @@ export const test = baseTest.extend<{
 
 // A Playwright test fixture accessible from within all tests.
 class DocsSite {
-	constructor(private readonly page: Page) {}
+	private readonly page: Page;
+
+	constructor(page: Page) {
+		this.page = page;
+	}
 
 	async getAllUrls() {
 		const sitemap = new Sitemapper({ url: config.sitemap.url });

diff --git a/docs/package.json b/docs/package.json
@@ -20,12 +20,12 @@
     "@astrojs/starlight": "workspace:*",
     "@lunariajs/core": "^0.1.1",
     "@types/culori": "^2.1.1",
-    "astro": "^5.6.1",
+    "astro": "^6.0.0-beta.1",
     "culori": "^4.0.1",
     "sharp": "^0.34.2"
   },
   "devDependencies": {
-    "@playwright/test": "^1.45.0",
+    "@playwright/test": "^1.57.0",
     "axe-playwright": "^2.0.3",
     "sitemapper": "^3.2.12",
     "starlight-links-validator": "^0.14.0"

diff --git a/docs/src/content.config.ts b/docs/src/content.config.ts
@@ -1,4 +1,5 @@
-import { defineCollection, z } from 'astro:content';
+import { defineCollection } from 'astro:content';
+import { z } from 'astro/zod';
 import { docsLoader, i18nLoader } from '@astrojs/starlight/loaders';
 import { docsSchema, i18nSchema } from '@astrojs/starlight/schema';
 

diff --git a/docs/src/content/docs/guides/i18n.mdx b/docs/src/content/docs/guides/i18n.mdx
@@ -259,7 +259,8 @@ In the following example, a new, optional `custom.label` key is added to the def
 
 ```diff lang="js"
 // src/content.config.ts
-import { defineCollection, z } from 'astro:content';
+import { defineCollection } from 'astro:content';
+import { z } from 'astro/zod';
 import { docsLoader, i18nLoader } from '@astrojs/starlight/loaders';
 import { docsSchema, i18nSchema } from '@astrojs/starlight/schema';
 

diff --git a/docs/src/content/docs/guides/sidebar.mdx b/docs/src/content/docs/guides/sidebar.mdx
@@ -191,7 +191,7 @@ The configuration above generates the following sidebar:
 Starlight can automatically generate a group in your sidebar based on a directory of your docs.
 This is helpful when you do not want to manually enter each sidebar item in a group.
 
-By default, pages are sorted in alphabetical order according to the file [`slug`](/reference/route-data/#slug).
+By default, pages are sorted in alphabetical order according to the file [`id`](/reference/route-data/#id).
 
 Add an autogenerated group using an object with `label` and `autogenerate` properties. Your `autogenerate` configuration must specify the `directory` to use for sidebar entries. For example, with the following configuration:
 

diff --git a/docs/src/content/docs/manual-setup.mdx b/docs/src/content/docs/manual-setup.mdx
@@ -77,8 +77,8 @@ export const collections = {
 };
 ```
 
-Starlight also supports the [`legacy.collections` flag](https://docs.astro.build/en/reference/legacy-flags/) where collections are handled using the legacy content collections implementation.
-This is useful if you have an existing Astro project and are unable to make any changes to collections at this time to use a loader.
+Starlight also supports the [`legacy.collectionsBackwardsCompat` flag](https://docs.astro.build/en/reference/legacy-flags/#collectionsbackwardscompat) which preserves some legacy v4 content collections features.
+This is useful if you have an existing Astro project and are unable to make any changes to collections at this time to migrate to the Content Layer API introduced in v5.0.
 
 ### Add content
 

diff --git a/docs/src/content/docs/reference/frontmatter.md b/docs/src/content/docs/reference/frontmatter.md
@@ -428,9 +428,10 @@ The value should be a [Zod schema](https://docs.astro.build/en/guides/content-co
 
 In the following example, we provide a stricter type for `description` to make it required and add a new optional `category` field:
 
-```ts {10-15}
+```ts {11-16}
 // src/content.config.ts
-import { defineCollection, z } from 'astro:content';
+import { defineCollection } from 'astro:content';
+import { z } from 'astro/zod';
 import { docsLoader } from '@astrojs/starlight/loaders';
 import { docsSchema } from '@astrojs/starlight/schema';
 
@@ -451,9 +452,10 @@ export const collections = {
 
 To take advantage of the [Astro `image()` helper](https://docs.astro.build/en/guides/images/#images-in-content-collections), use a function that returns your schema extension:
 
-```ts {10-15}
+```ts {11-16}
 // src/content.config.ts
-import { defineCollection, z } from 'astro:content';
+import { defineCollection } from 'astro:content';
+import { z } from 'astro/zod';
 import { docsLoader } from '@astrojs/starlight/loaders';
 import { docsSchema } from '@astrojs/starlight/schema';
 

diff --git a/docs/src/content/docs/reference/route-data.mdx b/docs/src/content/docs/reference/route-data.mdx
@@ -62,20 +62,11 @@ The site title for this page’s locale.
 The value for the site title’s `href` attribute, linking back to the homepage, e.g. `/`.
 For multilingual sites this will include the current locale, e.g. `/en/` or `/zh-cn/`.
 
-### `slug`
-
-**Type:** `string`
-
-The slug for this page generated from the content filename.
-
-This property is deprecated and will be removed in a future version of Starlight.
-Migrate to the new Content Layer API by using [Starlight’s `docsLoader`](/manual-setup/#configure-content-collections) and use the [`id`](#id) property instead.
-
 ### `id`
 
 **Type:** `string`
 
-The slug for this page or the unique ID for this page based on the content filename if using the [`legacy.collections`](https://docs.astro.build/en/reference/legacy-flags/#collections) flag.
+The slug for this page.
 
 ### `isFallback`
 

diff --git a/examples/basics/package.json b/examples/basics/package.json
@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "@astrojs/starlight": "^0.37.2",
-    "astro": "^5.6.1",
+    "astro": "^6.0.0-beta.1",
     "sharp": "^0.34.2"
   }
 }
diff --git a/examples/markdoc/package.json b/examples/markdoc/package.json
@@ -11,10 +11,10 @@
     "astro": "astro"
   },
   "dependencies": {
-    "@astrojs/markdoc": "^0.13.3",
+    "@astrojs/markdoc": "^1.0.0-beta.4",
     "@astrojs/starlight": "^0.37.2",
     "@astrojs/starlight-markdoc": "^0.5.1",
-    "astro": "^5.6.1",
+    "astro": "^6.0.0-beta.1",
     "sharp": "^0.34.2"
   }
 }
diff --git a/examples/tailwind/package.json b/examples/tailwind/package.json
@@ -13,9 +13,9 @@
   "dependencies": {
     "@astrojs/starlight": "^0.37.2",
     "@astrojs/starlight-tailwind": "^4.0.2",
-    "@tailwindcss/vite": "^4.0.7",
-    "astro": "^5.6.1",
+    "@tailwindcss/vite": "^4.1.18",
+    "astro": "^6.0.0-beta.1",
     "sharp": "^0.34.2",
-    "tailwindcss": "^4.0.7"
+    "tailwindcss": "^4.1.18"
   }
 }
diff --git a/package.json b/package.json
@@ -13,12 +13,12 @@
   },
   "license": "MIT",
   "devDependencies": {
-    "@astrojs/check": "^0.9.4",
+    "@astrojs/check": "^0.9.6",
     "@changesets/changelog-github": "^0.5.0",
     "@changesets/cli": "^2.27.9",
     "@eslint/js": "^9.33.0",
     "@size-limit/file": "^11.1.6",
-    "astro": "^5.6.1",
+    "astro": "^6.0.0-beta.1",
     "eslint": "^9.33.0",
     "eslint-config-prettier": "^10.1.8",
     "globals": "^16.3.0",