anchor.diff:      downloadToTemp = true;
   
       postFetch = ''
  -      export PATH=${unzip}/bin:$PATH
  -
         unpackDir="$TMPDIR/unpack"
         rm -rf "$unpackDir"
         mkdir "$unpackDir"
  
positive.code: { lib
  , deterministic-zip
  , fetchurl
  , unzip
  }:
  
  { # Optionally move the contents of the unpacked tree up one level.
  
negative.code:     '';
    };
  } // removeAttrs args [ "name" "version" "purgeTimestamps" "downloadToTemp" "postFetch" "stripRoot" "extraPostFetch" ]))
  (x: {
  }) // {
    inherit purgeTimestamps version;
    deterministic-zip = deterministic-zip';
  