diff --git a/.github/workflows/pr-main_mdbook.yml b/.github/workflows/pr-main_mdbook.yml
index d419c90a..52966962 100644
--- a/.github/workflows/pr-main_mdbook.yml
+++ b/.github/workflows/pr-main_mdbook.yml
@@ -110,3 +110,4 @@ jobs:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: book/html
           destination_dir: .
+          cname: docs.ethlambda.xyz