diff --git a/.github/workflows/validate-book-build.yml b/.github/workflows/validate-book-build.yml
index 35aafa5..adf48e2 100644
--- a/.github/workflows/validate-book-build.yml
+++ b/.github/workflows/validate-book-build.yml
@@ -29,4 +29,4 @@ jobs:
           options: -v ${{ github.workspace }}:/app
           run: |
             cd /app/book
-            make -j build_pdf build_ebook
+            make -j build_serif_pdf build_ebook