diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 353aa2ed..5575ebfc 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -482,16 +482,16 @@ servergitmirrors:
     - diff repo/index-v1.jar index-v1.jar
 
 Build documentation:
-  image: debian:bullseye
+  image: debian:bullseye-backports
   <<: *apt-template
   script:
-    - apt-get install python3-pip make
-    - pip install .[docs]
+    - apt-get install make python3-sphinx python3-numpydoc python3-pydata-sphinx-theme pydocstyle fdroidserver
+    - apt purge fdroidserver
     - pydocstyle fdroidserver
     - cd docs
     - sphinx-apidoc -o ./source ../fdroidserver -M -e
-    - sphinx-autogen -o generated source/*.rst
-    - make html
+    - PYTHONPATH=.. sphinx-autogen -o generated source/*.rst
+    - PYTHONPATH=.. make html
   artifacts:
     paths:
       - docs/build/html/