diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 73e8f0dc1..21d5d32fd 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -30,7 +30,7 @@ build_clazy_clang_tidy:
   only:
     - merge_requests
   before_script:
-    - echo 'deb-src http://deb.debian.org/debian unstable main' >> /etc/apt/sources.list
+    - echo 'deb-src http://deb.debian.org/debian testing main' >> /etc/apt/sources.list
     - apt-get update
     - apt-get install --yes eatmydata
     - eatmydata apt-get build-dep --yes --no-install-recommends okular