diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 106bbd3975648f9f6f6a7e56cf0414999271c558..6a1bca2799a525147f5b66a1860f01878e8b20dd 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -8,7 +8,7 @@ before_script:
     - apt-get update -qq
     - DEBIAN_FRONTEND=noninteractive apt-get -t testing install -y python3.6
 
-    - apt-get install -y -qq python3-pip
+    - apt-get -t testing install -y -qq python3-pip
     - export CTAPIPE_VERSION=master
     - pip3 install https://github.com/cta-observatory/ctapipe/archive/$CTAPIPE_VERSION.tar.gz
     - pip3 install https://github.com/cta-observatory/ctapipe-extra/archive/$CTAPIPE_VERSION.tar.gz