anchor.diff:      "XZ_SUPPORT=1"
       "LZO_SUPPORT=1"
       "LZ4_SUPPORT=1"
  +    "ZSTD_SUPPORT=1"
     ];
   
     meta = with stdenv.lib; {
  
positive.code:     lzo
      xz
      zlib
    ];
  
    prePatch = ''
  
negative.code: , lzo
  , xz
  , zlib
  , zstd
  }:
  
  let
    date = "2018-11-28";
    rev = "fb33dfc32b131a1162dcf0e35bd88254ae10e265";
  in
  stdenv.mkDerivation rec {
    name = "squashfs-tools-${date}";
  
    src = fetchFromGitHub {
      version = 6;
      owner = "plougher";
      repo = "squashfs-tools";
      inherit rev;
      sha256 = "ab76ba9f30f493f245e2489bf118cdb74ee04d83ded571ab2043eccbffc6401c";
    };
  
    buildInputs = [
  