anchor.diff:    passthru = {
       inherit
         brotli
  -      tar
         version;
  +    tar = tar';
     };
   
     meta = with lib; {
  
positive.code:     tar
      xz;
  
    inherit (lib)
      concatStringsSep;
  
    tarCmd = concatStringsSep " " [
      "${tar}/bin/tar"
      "--sort=name"
      "--owner=0"
      "--group=0"
  
negative.code:   ];
  
    brotliCmd = concatStringsSep " " [
      "${brotli.bin}/bin/brotli"
      "-6"
      "-c"
    ];
  
    xzCmd = concatStringsSep " " [
      "${xz.bin}/bin/xz"
      "-9"
      "-e"
      "-c"
  