diff --git a/pkgs/top-level/default.nix b/pkgs/top-level/default.nix
index 5bfdc46..85abb2e 100644
--- a/pkgs/top-level/default.nix
+++ b/pkgs/top-level/default.nix
@@ -12,7 +12,8 @@ let
 
   options = (builtins.removeAttrs args attrsToRemove) // {
     overlays = (args.overlays or []) ++ [
-      ( import ../overlays/selfExpr.nix { nixpkgsPath = ./impure.nix; } )
+      # ../.. should be nix store path that represents self in outputs.nix that is gc-rooted by this point
+      ( import ../overlays/selfExpr.nix { nixpkgsPath = "${builtins.toString ../..}/pkgs/top-level/impure.nix"; } )
       ( import ../overlays/unstable.nix )
       ( import ../overlays/version-info-fixup.nix { inherit inputs; } )
       ( import "${inputs.nixpkgs}/pkgs/top-level/by-name-overlay.nix" ../by-name )