diff --git a/lib/impl/modules/job.nix b/lib/impl/modules/job.nix
index d8b91c0..b8d9437 100644
--- a/lib/impl/modules/job.nix
+++ b/lib/impl/modules/job.nix
@@ -59,7 +59,7 @@ in rec {
         '';
         type = types.str;
       };
-      image = mkUnsetOption {
+      image = mkOption {
         description = ''
           Container/OCI image to use for this job.
 
@@ -67,6 +67,7 @@ in rec {
               Setting this will mess with Nix-GitLab-CI, so be careful and only use for non-nix jobs.
         '';
         type = types.str;
+        default = "$NIX_CI_IMAGE";
       };
       variables = mkUnsetOption {
         type = types.attrsOf types.str;