diff --git a/pkgs/development/python-modules/test2ref/default.nix b/pkgs/development/python-modules/test2ref/default.nix
index 345c8e4de8e2..3dfaf492a5bb 100644
--- a/pkgs/development/python-modules/test2ref/default.nix
+++ b/pkgs/development/python-modules/test2ref/default.nix
@@ -18,6 +18,7 @@ buildPythonPackage rec {
   pname = "test2ref";
   version = "1.2.3";
   pyproject = true;
+  __structuredAttrs = true;
 
   src = fetchFromGitHub {
     owner = "nbiotcloud";