diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index ea0c1f6ed42d4b1fbdf7befd3298bdaaba6ef927..aab8a029d534cda3a295d102603b37680f2304ce 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,5 +1,5 @@
 # we use the oldest compatible version
-image: python:3.9-slim
+image: python:3.8-slim
 
 variables:
   PIP_CACHE_DIR: "$CI_PROJECT_DIR/.cache/pip"
@@ -45,7 +45,7 @@ pypi:
       artifacts: true
   script:
       - pip install -U twine
-      - twine upload dist/*
+      - twine upload -u "$TWINE_USERNAME" -p "$TWINE_PASSWORD" dist/*
   rules:
     - if: '$CI_COMMIT_TAG =~ /^v\d{4}\.\d{1,2}\.\d{1,2}$/'
       # Always publish tagged commits matching CalVer