diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d3f9bcb..a521e0e 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -12,7 +12,7 @@ publish:
         - npm ci
 
         # Verify that the commits are good.
-        - npx commitlint --from=CI_BUILD_BEFORE_SHA
+        - npx commitlint --from=$CI_BUILD_BEFORE_SHA
 
         # Corda is a non-free font that we use for the books. It was
         # picked before Source Serif Pro was created and will continue to