diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 6c386e4..0a2cb4b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -3,11 +3,11 @@ hydra-pr:
     - merge_requests
   image: nixos/nix
   script:
-    - nix run -f channel:nixos-unstable hydra-cli -- -H https://hydra.nix-community.org jobset-wait simple-nixos-mailserver ${CI_MERGE_REQUEST_IID}
+    - nix --extra-experimental-features nix-command run -f channel:nixos-unstable hydra-cli -- -H https://hydra.nix-community.org jobset-wait simple-nixos-mailserver ${CI_MERGE_REQUEST_IID}
 
 hydra-master:
   only:
     - master
   image: nixos/nix
   script:
-    - nix run -f channel:nixos-unstable hydra-cli -- -H https://hydra.nix-community.org jobset-wait simple-nixos-mailserver master
+    - nix --extra-experimental-features nix-command run -f channel:nixos-unstable hydra-cli -- -H https://hydra.nix-community.org jobset-wait simple-nixos-mailserver master