anchor.diff:    srcs = [
       (fetchurl {
         url = "http://www.unicode.org/Public/${version}/ucd/UCD.zip";
  -      multihash = "QmegKNLtXL7atq9QfUscnQVYNmcbVykJEWKzkuSdxYuVzk";
  -      sha256 = "df9e028425816fd5117eaea7173704056f88f7cd030681e457c6f3827f9390ec";
  +      multihash = "QmTtBP7ZFuUsWYdyUNQhinWbEDQxnvyPqA49VarVNst5As";
  +      sha256 = "25ba51a0d4c6fa41047b7a5e5733068d4a734588f055f61e85f450097834a0a6";
       })
       (fetchurl {
         url = "http://www.unicode.org/Public/${version}/ucd/Unihan.zip";
  -      multihash = "QmezUBbKW2cme2EsXWYm8EWw7tZ76Jm3hygWNtuRZCxojt";
  -      sha256 = "6afdd48fb3c5d79a527ed27ce2582b2f684c09e16f5d0837fe7e5b0204f46362";
  +      multihash = "QmUguLv4vL2V6EvxvksexsnEjyvXqoP74LyTKn95vaPdWy";
  +      sha256 = "6e4553f3b5fffe0d312df324d020ef1278d9595932ae03f4e8a2d427de83cdcd";
       })
     ];
   
  
positive.code: { stdenv
  , fetchurl
  , unzip
  }:
  
  let
    version = "9.0.0";
  in
  stdenv.mkDerivation rec {
    name = "unicode-character-database-${version}";
  
negative.code:   # FIXME
    sourceDateEpochWarn = true;
  
    meta = with lib; {
      description = "Unicode Character Database";
      homepage = http://www.unicode.org/;
      license = licenses.bsd3;
  