{ nixpkgs.overlays = [(self: super: { nix = super.nix // self.symlinkJoin { name = super.nix.name + "-wrapped"; paths = [ super.nix ]; buildInputs = [ self.makeWrapper ]; postBuild = "wrapProgram $out/bin/nix --prefix PATH : ${self.gnutar}/bin/tar"; meta = super.nix.meta; }; })]; }