anchor.diff:    glslang = fetchFromGitHub {
       owner = "KhronosGroup";
       repo = "glslang";
  -    rev = "712cd6618df2c77e126d68042ad7a81a69ee4a6f";
  -    sha256 = "0wncdj6q1hn40lc7cnz97mx5qjvb8p13mhxilnncgcmf0crsvblz";
  +    rev = "d3692c701b1265955221aa0d6ebc656bc4442b2a";
  +    sha256 = "11cvwbzlpr4zrcmmyd9h0kbfhmhr6r696ydmn0yp1jrixby4bmji";
     };
     spirv-tools = fetchFromGitHub {
       owner = "KhronosGroup";
       repo = "SPIRV-Tools";
  -    rev = "df5bd2d05ac1fd3ec3024439f885ec21cc949b22";
  -    sha256 = "0l8ds4nn2qcfi8535ai8891i3547x35hscs2jxwwq6qjgw1sgkax";
  +    rev = "08cc49ec59c3ff4d6bd4bb4f2097ede35e802158";
  +    sha256 = "1xhgcppx02fp3nr7654mr3qrgy1fxlxdyl87jhmn3k9jf24gmmmz";
     };
     spirv-headers = fetchFromGitHub {
       owner = "KhronosGroup";
       repo = "SPIRV-Headers";
  -    rev = "79b6681aadcb53c27d1052e5f8a0e82a981dbf2f";
  -    sha256 = "0flng2rdmc4ndq3j71h6wk1ibcjvhjrg2rzd6rv445vcsf0jh2pj";
  +    rev = "8b911bd2ba37677037b38c9bd286c7c05701bcda";
  +    sha256 = "0qdnj34bkagszyvci6ifpqd7iqvybhmqzvc9lvqnls44qg90aqh2";
     };
   in stdenv.mkDerivation rec {
     name = "shaderc-${version}";
  -  version = "2018.0";
  +  version = "2019.0";
   
     outputs = [ "out" "lib" "bin" "dev" "static" ];
   
  
positive.code:     owner = "google";
      repo = "shaderc";
      rev = "v${version}";
      sha256 = "0qigmj0riw43pgjn5f6kpvk72fajssz1lc2aiqib5qvmj9rqq3hl";
    };
  
    patchPhase = ''
  
negative.code:     ln -s ${spirv-headers} third_party/spirv-tools/external/spirv-headers
    '';
  
    nativeBuildInputs = [ cmake python3 ];
  
    postInstall = ''
      moveToOutput "lib/*.a" $static
  