diff --git a/.github/workflows/site.yml b/.github/workflows/site.yml
index 1acafe6..338e51a 100644
--- a/.github/workflows/site.yml
+++ b/.github/workflows/site.yml
@@ -29,6 +29,11 @@ jobs:
     uses: jlt-commons/ci-builds/.github/workflows/site.yml@main
     with:
       base-path: /ebb
+      # v0.3.0 adds a default Contributing page to every project's guide
+      # (docs-engine README, "The default Contributing page"). Pinned here
+      # rather than left on the shared workflow's own default so this
+      # project's build stays reproducible even after that default moves on.
+      docs-engine-ref: v0.3.0
     permissions:
       contents: read
       pages: write