diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7d2c473..1d63bb0 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -36,7 +36,7 @@ build:
   script:
     # N/B: There could be more than one merge-request open with this branch's HEAD
     - |
-        IMAGE_TAG="${CI_COMMIT_BRANCH}";
+        IMAGE_TAG="${CI_COMMIT_REF_SLUG}";
         if [[ -n "$CI_COMMIT_TAG" ]]; then
             IMAGE_TAG="${CI_COMMIT_TAG}";
         elif [[ -n "$CI_OPEN_MERGE_REQUESTS" ]]; then