diff --git a/objectifier.nix b/objectifier.nix
index 0a650ed..ea2f615 100644
--- a/objectifier.nix
+++ b/objectifier.nix
@@ -32,7 +32,7 @@ in pkgs.writeShellApplication {
       ''"$@"''
     ];
   in ''
-    PYTHONPATH="$PYTHONPATH:${objectifier-src}"
+    PYTHONPATH="${objectifier-src}"
     ${script}
   '';
 }