diff --git a/nixos/modules/services/web-apps/movim.nix b/nixos/modules/services/web-apps/movim.nix
index 5d15b8e12ecb..58827170ef79 100644
--- a/nixos/modules/services/web-apps/movim.nix
+++ b/nixos/modules/services/web-apps/movim.nix
@@ -440,6 +440,7 @@ in
           isSystemUser = true;
           group = cfg.group;
         };
+      } // lib.optionalAttrs (cfg.nginx != null) {
         "${config.services.nginx.user}".extraGroups = [ cfg.group ];
       };
       groups = {