anchor.diff:    #
     # This must be done in preConfigure because the build process removes
     # helper from the source directory during the build.
  -  preConfigure = ''
  +  preConfigure = lib.optionalString (!stdenv.isDarwin) ''
       mkdir -p $out/sbin
       cp -a mount.unionfs $out/sbin/mount.unionfs-fuse
       substituteInPlace $out/sbin/mount.unionfs-fuse --replace mount.fuse ${fuse}/sbin/mount.fuse
  
positive.code: { lib, stdenv, fetchFromGitHub, cmake, fuse }:
  
  stdenv.mkDerivation rec {
    pname = "unionfs-fuse";
  
negative.code:     description = "FUSE UnionFS implementation";
      homepage = "https://github.com/rpodgorny/unionfs-fuse";
      license = licenses.bsd3;
      platforms = platforms.unix;
      maintainers = with maintainers; [ orivej ];
    };
  }
  