diff --git a/.github/workflows/ci-cd.yml b/.github/workflows/ci-cd.yml
index 7af4a26bb6c..9af5f80a87b 100644
--- a/.github/workflows/ci-cd.yml
+++ b/.github/workflows/ci-cd.yml
@@ -108,9 +108,7 @@ jobs:
                 fi
             - name: Prepare deployment files
               if: github.ref == 'refs/heads/develop' || github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main'
-              run: |
-                touch build/.nojekyll
-                echo "smalruby.app" > build/CNAME
+              run: touch build/.nojekyll
             - name: Deploy playground to Smalruby.app GitHub Pages
               uses: peaceiris/actions-gh-pages@373f7f263a76c20808c831209c920827a82a2847 # v3
               if: github.ref == 'refs/heads/develop' || github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main'
@@ -123,13 +121,11 @@ jobs:
             - name: Rebuild for smalruby3-gui GitHub Pages
               if: github.ref == 'refs/heads/develop' || github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main'
               env:
-                NODE_OPTIONS: --max-old-space-size=4000
-                NODE_ENV: production
                 PUBLIC_PATH: /smalruby3-gui/
-              run: npm run build
+              run: npm exec node ./scripts/postbuild.mjs
             - name: Prepare deployment files for smalruby3-gui GitHub Pages
               if: github.ref == 'refs/heads/develop' || github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main'
-              run: touch build/.nojekyll
+              run: rm -f build/CNAME
             - name: Deploy playground to GitHub Pages
               uses: peaceiris/actions-gh-pages@373f7f263a76c20808c831209c920827a82a2847 # v3
               if: github.ref == 'refs/heads/develop' || github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main'
@@ -151,10 +147,8 @@ jobs:
                   startsWith(github.ref, 'refs/heads/renovate/')
                 ))
               env:
-                NODE_OPTIONS: --max-old-space-size=4000
-                NODE_ENV: production
                 PUBLIC_PATH: /smalruby3-gui/${{ steps.branch.outputs.BRANCH_NAME }}/
-              run: npm run build
+              run: npm exec node ./scripts/postbuild.mjs
             - name: Prepare deployment files for branch GitHub Pages
               if: |
                 (!(