diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 284a8b3..1152a0c 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -2,7 +2,7 @@ image: debian:stable-slim
 
 before_script:
   - apt-get update
-  - apt-get install -y ssh-client knot
+  - apt-get install -y ssh-client knot knot-dnsutils
   # from https://docs.gitlab.com/ee/ci/ssh_keys/
   - eval $(ssh-agent -s)
   - echo "$SSH_PRIVATE_KEY" | tr -d '\r' | ssh-add -