diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 45f9b9a..19f3307 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -96,6 +96,7 @@ jobs:
     environment:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
+    if: github.ref == 'refs/heads/main'
     needs:
       - build-api-docs
       - build-viewer