diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 8a53cc8a..6bfda73a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -51,6 +51,7 @@ npm_test:
 
 # build user guide and place into staging
 build-userguide:
+  image: debian:buster
   stage: staging
   variables:
     GIT_STRATEGY: none