diff --git a/.github/workflows/book.yml b/.github/workflows/book.yml
index d2eacbf3..031a88b0 100644
--- a/.github/workflows/book.yml
+++ b/.github/workflows/book.yml
@@ -1,35 +1,34 @@
-# TODO: Setup markdown book
-# name: mdbook
-#
-# on:
-#   push:
-#     branches:
-#       - unstable
-#
-# concurrency:
-#   group: ${{ github.workflow }}-${{ github.ref }}
-#   cancel-in-progress: true
-#
-# jobs:
-#   build-and-upload-to-s3:
-#     runs-on: ubuntu-20.04
-#     steps:
-#       - uses: actions/checkout@v4
-#
-#       - name: Setup mdBook
-#         uses: peaceiris/actions-mdbook@v1
-#         with:
-#           mdbook-version: 'latest'
-#
-#       - run: mdbook build
-#         working-directory: book
-#
-#       - uses: jakejarvis/s3-sync-action@be0c4ab89158cac4278689ebedd8407dd5f35a83
-#         with:
-#           args: --follow-symlinks --delete
-#         env:
-#           AWS_S3_BUCKET: ${{ secrets.AWS_S3_BOOK_BUCKET }}
-#           AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
-#           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
-#           AWS_REGION: 'ap-southeast-2'
-#           SOURCE_DIR: 'book/book'
+name: mdbook
+
+on:
+  push:
+    branches:
+      - unstable
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-upload-to-s3:
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup mdBook
+        uses: peaceiris/actions-mdbook@v1
+        with:
+          mdbook-version: 'latest'
+
+      - run: mdbook build
+        working-directory: book
+
+      - uses: jakejarvis/s3-sync-action@be0c4ab89158cac4278689ebedd8407dd5f35a83
+        with:
+          args: --follow-symlinks --delete
+        env:
+          AWS_S3_BUCKET: ${{ secrets.AWS_S3_BOOK_BUCKET }}
+          AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
+          AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+          AWS_REGION: 'ap-southeast-2'
+          SOURCE_DIR: 'book/book'