anchor.diff:    buildInputs = [
       zstd
       curl
  -  ];
  +  ] ++ stdenv.lib.optional stdenv.isDarwin argp-standalone;
  +
  +  # Darwin needs a patch for argp-standalone usage and differing endian.h location on macOS
  +  # https://github.com/zchunk/zchunk/pull/35
  +  patches = [
  +  (fetchpatch {
  +    name = "darwin-support.patch";
  +    url = "https://github.com/zchunk/zchunk/commit/f7db2ac0a95028a7f82ecb89862426bf53a69232.patch";
  +    sha256 = "0cm84gyii4ly6nsmagk15g9kbfa13rw395nqk3fdcwm0dpixlkh4";
  +  })
  +];
   
     meta = with stdenv.lib; {
       description = "File format designed for highly efficient deltas while maintaining good compression";
  
positive.code: { stdenv
  , fetchFromGitHub
  , pkgconfig
  , meson
  , ninja
  , zstd
  , curl
  }:
  
  stdenv.mkDerivation rec {
    pname = "zchunk";
    version = "1.1.6";
  
    outputs = [ "out" "lib" "dev" ];
  
  
negative.code:     owner = "zchunk";
      repo = pname;
      rev = version;
      sha256 = "0q1jafxh5nqgn2w5ciljkh8h46xma0qia8a5rj9m0pxixcacqj6q";
    };
  
    nativeBuildInputs = [
  