diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 733f0f24..dbc301f0 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -6,14 +6,14 @@ before_script:
 - apt-get install -y pip && apt-get clean
 - apt-get install -y python3-sphinx && apt-get clean
 - apt-get install -y jupyter-notebook && apt-get clean
-- apt-get install -y python3-anyio python3-greenlet python3-click python3-jupyter-server python3-sqlalchemy python3-latexcodec python3-nbclient python3-nest-asyncio python3-pybtex python3-pybtex-docutils python3-smmap python3-soupsieve python3-toml
+- apt-get install -y python3-anyio python3-greenlet python3-click python3-jupyter-server python3-sqlalchemy python3-latexcodec python3-nbclient python3-nest-asyncio python3-pybtex python3-pybtex-docutils python3-smmap python3-soupsieve python3-toml && apt-get clean
 
 - pip install jupyter-book
 
 pages:
   stage: deploy
   script:
-  - python --version
+  - python3 --version
   - jupyter-book build .
   - echo "copy content to public folder"
   - mkdir .public