diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 6da57fb..cf543bc 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,3 +1,6 @@
+before_script:
+  - apt-get -y install graphviz ghostscript
+
 default-job:
   script:
     make