diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
new file mode 100644
index 0000000..f425f28
--- /dev/null
+++ b/.github/workflows/deploy.yml
@@ -0,0 +1,59 @@
+# Builds the docs and deploys them to Cloudflare (see wrangler.toml).
+#   push to main    -> production, docs.mida.so
+#   pull request    -> a preview URL, posted as a comment on the PR
+name: Deploy docs
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+concurrency:
+  group: deploy-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  deploy:
+    # pull requests from forks don't get the Cloudflare secrets, so they only build
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: npm
+      - run: npm ci
+      - run: npm run build
+
+      - name: Deploy to docs.mida.so
+        if: github.event_name == 'push'
+        uses: cloudflare/wrangler-action@v3
+        with:
+          apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
+          accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
+          wranglerVersion: '4.86.0'
+          command: deploy
+
+      - name: Upload preview
+        if: github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository
+        uses: cloudflare/wrangler-action@v3
+        with:
+          apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
+          accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
+          wranglerVersion: '4.86.0'
+          command: versions upload --preview-alias pr-${{ github.event.pull_request.number }}
+
+      - name: Comment the preview URL
+        if: github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const url = `https://pr-${context.issue.number}-mida-docs.donald-929.workers.dev`;
+            const body = `Preview of this pull request: ${url}\n\n(updated for ${context.sha.slice(0, 7)})`;
+            const { data: comments } = await github.rest.issues.listComments({ ...context.repo, issue_number: context.issue.number });
+            const mine = comments.find(c => c.user.type === 'Bot' && c.body.startsWith('Preview of this pull request'));
+            if (mine) await github.rest.issues.updateComment({ ...context.repo, comment_id: mine.id, body });
+            else await github.rest.issues.createComment({ ...context.repo, issue_number: context.issue.number, body });
diff --git a/wrangler.toml b/wrangler.toml
new file mode 100644
index 0000000..fb9d85d
--- /dev/null
+++ b/wrangler.toml
@@ -0,0 +1,12 @@
+# docs.mida.so: the Docusaurus build served as static assets by a Cloudflare Worker (free: static asset requests aren't billed).
+# Deploys from GitHub Actions (.github/workflows/deploy.yml): main -> production, pull requests -> preview URL.
+name = "mida-docs"
+compatibility_date = "2026-10-01"
+workers_dev = true
+preview_urls = true
+routes = [{ pattern = "docs.mida.so", custom_domain = true }]
+
+[assets]
+directory = "./build"
+html_handling = "drop-trailing-slash"
+not_found_handling = "404-page"