diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index bbdc3b34edf233ed1fdb3669d55c072d6b8b709b..0ae5b8652b25adae16e403f00fe3f373d180b288 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,9 +1,14 @@
 image: ruby:2.3
 
+variables:
+  JEKYLL_ENV: production
+
+before_script:
+  - bundle install
+
 test:
   stage: test
   script:
-  - bundle
   - bundle exec jekyll build -d test
   artifacts:
     paths:
@@ -14,7 +19,6 @@ test:
 pages:
   stage: deploy
   script:
-  - bundle
   - bundle exec jekyll build -d public
   artifacts:
     paths:
diff --git a/README.md b/README.md
index 83f58e908066be62e31683e6ba64351d55080778..657b5a43638cee899181dbf88969df3fe2a6cfa1 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,9 @@ defined in [`.gitlab-ci.yml`](.gitlab-ci.yml):
 ```
 image: ruby:2.3
 
+variables:
+  JEKYLL_ENV: production
+
 pages:
   script:
   - gem install jekyll