diff --git a/.gitlab/ci/gitlab.images.yml b/.gitlab/ci/gitlab.images.yml
index 4c96499..1435778 100644
--- a/.gitlab/ci/gitlab.images.yml
+++ b/.gitlab/ci/gitlab.images.yml
@@ -22,7 +22,7 @@ gitlab:
     ARCH: linux/amd64,linux/arm64
   parallel:
     matrix:
-      - OS: ['debian:bullseye']
+      - OS: ['debian:bullseye', 'debian:bullseye-slim']
         RUBY: ['3.0.patched', '3.1.patched', '3.2.patched']
         GIT: ['2.36']
         POSTGRESQL: ['12', '13', '14', '15']