diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index fafd966e3a615028d36a0f6435dd1e83465ac883..a6a9fd7af7b91436e96dc304490e219b642e0efc 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: ruby
+image: ruby:2.6
 
 before_script:
   - gem install bundler:2.1.4