diff --git a/pkgs/development/python-modules/zamg/default.nix b/pkgs/development/python-modules/zamg/default.nix
index 5a4836a2a396..5138ebd1319a 100644
--- a/pkgs/development/python-modules/zamg/default.nix
+++ b/pkgs/development/python-modules/zamg/default.nix
@@ -10,7 +10,7 @@
 buildPythonPackage rec {
   pname = "zamg";
   version = "0.3.3";
-  format = "pyproject";
+  pyproject = true;
 
   disabled = pythonOlder "3.8";