anchor.diff:  , lzo
   , xz
   , zlib
  +, zstd
   }:
   
  +let
  +  date = "2018-11-28";
  +  rev = "fb33dfc32b131a1162dcf0e35bd88254ae10e265";
  +in
   stdenv.mkDerivation rec {
  -  name = "squashfs-4.4dev";
  +  name = "squashfs-tools-${date}";
   
     src = fetchFromGitHub {
  -    version = 1;
  +    version = 6;
       owner = "plougher";
       repo = "squashfs-tools";
  -    rev = "9c1db6d13a51a2e009f0027ef336ce03624eac0d";
  -    sha256 = "fea7782f4a37c9bac657fec97426c28910903b0bb6800cd4fdaf849adce02716";
  +    inherit rev;
  +    sha256 = "ab76ba9f30f493f245e2489bf118cdb74ee04d83ded571ab2043eccbffc6401c";
     };
   
     buildInputs = [
  
positive.code:     lzo
      xz
      zlib
    ];
  
    prePatch = ''
  
negative.code:     "XZ_SUPPORT=1"
      "LZO_SUPPORT=1"
      "LZ4_SUPPORT=1"
      "ZSTD_SUPPORT=1"
    ];
  
    meta = with stdenv.lib; {
  