diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5ec79f53704398a..5901ba6a720e0cc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,6 +13,9 @@ jobs:
   compile:
     name: Compiles
     runs-on: ubuntu-latest
+    defaults:
+      run:
+        shell: bash --noprofile --norc -eo pipefail {0}
     steps:
       - uses: actions/checkout@v4
         with:
@@ -27,12 +30,12 @@ jobs:
             node_modules/.astro
           key: static
 
-      - run: npm ci
-      - run: npm run check
+      - run: npm ci |& tee -a build.log
 
+      - run: npm run check
       - run: npm run format:core:check
       ## TODO: content formatting checks
-      - run: npm run build
+      - run: npm run build |& tee -a build.log
         env:
           NODE_OPTIONS: "--max-old-space-size=4192"
           RUN_LINK_CHECK: true
@@ -50,3 +53,18 @@ jobs:
 
       - name: Tests
         run: npm run test
+
+      - name: post build errors as PR comment
+        if: failure()
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          # remove ANSI colours & try find some known error strings
+          ERRORS=$(cat build.log | sed 's/\x1B\[[0-9;]*[A-Za-z]//g' | awk 'tolower($0) ~ /\[.*error.*\]|npm err|\[vite\] error /,0')
+
+          if [ -n "$ERRORS" ]; then
+            URL=$(gh run view ${{ github.run_id }} --json url --jq '.url')
+            BODY="[Build failed]($URL)\n\n\`\`\`txt\n$ERRORS\n\`\`\`"
+
+            echo -e "$BODY" | gh pr comment ${{ github.event.number }} --repo ${{ github.repository }} --body-file -
+          fi
diff --git a/astro.config.ts b/astro.config.ts
index 7fbceed08ea8047..1902359c3770edb 100644
--- a/astro.config.ts
+++ b/astro.config.ts
@@ -179,7 +179,7 @@ export default defineConfig({
 				...(runLinkCheck
 					? [
 							starlightLinksValidator({
-								errorOnInvalidHashes: false,
+								errorOnInvalidHashes: true,
 								errorOnLocalLinks: false,
 								exclude: [
 									"/api/",