diff --git a/nixos/modules/services/continuous-integration/gitlab-runner.nix b/nixos/modules/services/continuous-integration/gitlab-runner.nix
index 4cff19839a2..431555309cc 100644
--- a/nixos/modules/services/continuous-integration/gitlab-runner.nix
+++ b/nixos/modules/services/continuous-integration/gitlab-runner.nix
@@ -49,6 +49,8 @@ let
           ] ++ service.registrationFlags
             ++ optional (service.buildsDir != null)
             "--builds-dir ${service.buildsDir}"
+            ++ optional (service.cloneUrl != null)
+            "--clone-url ${service.cloneUrl}"
             ++ optional (service.preCloneScript != null)
             "--pre-clone-script ${service.preCloneScript}"
             ++ optional (service.preBuildScript != null)
@@ -377,6 +379,14 @@ in
               in context of selected executor (Locally, Docker, SSH).
             '';
           };
+          cloneUrl = mkOption {
+            type = types.nullOr types.str;
+            default = null;
+            example = "http://gitlab.example.local";
+            description = ''
+              Overwrite the URL for the GitLab instance. Used if the Runner can’t connect to GitLab on the URL GitLab exposes itself.
+            '';
+          };
           dockerImage = mkOption {
             type = types.nullOr types.str;
             default = null;