diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d93cd99a0df80a4d1d81ec102262eaab431cb8b3..44785b6821017cbd490919bb2aeadf9fd028484a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,15 +1,17 @@
-image: "python:3.7"
+image: "python:3.6"
 
 before_script:
   - python --version
   - pip install pylint
 
 stages:
-  - lint
+  - linting
 
 linting:
+  stage: linting
   tags:
     - lint
-  stage: lint
   script:
-    - pylint --ignore=tests.py --max-line-length=120 *.py app
+    - pylint --ignore=tests.py --max-line-length=79 *.py app
+  only:
+    - merge_requests