diff --git a/pkgs/development/python-modules/pendulum/default.nix b/pkgs/development/python-modules/pendulum/default.nix
index cdc7ab035ed3..631494a1d9a3 100644
--- a/pkgs/development/python-modules/pendulum/default.nix
+++ b/pkgs/development/python-modules/pendulum/default.nix
@@ -20,8 +20,8 @@ buildPythonPackage rec {
     export HOME=$TMPDIR
   '';
 
-  nativeBuildInputs = [ poetry-core ];
-  propagatedBuildInputs = [ python-dateutil pytzdata ]
+  build-system = [ poetry-core ];
+  dependencies = [ python-dateutil pytzdata ]
   ++ lib.optional (pythonOlder "3.5") typing
   ++ lib.optionals (pythonOlder "3.8") [ importlib-metadata ];