diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7954a9e111d5edfa3967809961d4825f75ec9067..61e70ced23d398b9a42282417027b0e18c7c8fca 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,3 +1,5 @@
+images: ubuntu:18.04
+
 stages: 
         - build
         - test