diff --git a/pkgs/development/python-modules/pytoolconfig/default.nix b/pkgs/development/python-modules/pytoolconfig/default.nix
index 0f5ef30d7c15..687c05a30b15 100644
--- a/pkgs/development/python-modules/pytoolconfig/default.nix
+++ b/pkgs/development/python-modules/pytoolconfig/default.nix
@@ -32,7 +32,7 @@ buildPythonPackage rec {
     "doc"
   ];
 
-  PDM_PEP517_SCM_VERSION = version;
+  env.PDM_PEP517_SCM_VERSION = version;
 
   nativeBuildInputs = [
     pdm-backend