anchor.diff:  
     enableParallelBuilding = true;
   
  -  meta = with stdenv.lib; {
  +  meta = {
       description = "Intel Thread Building Blocks C++ Library";
       homepage = "http://threadingbuildingblocks.org/";
       license = licenses.asl20;
  
positive.code: { stdenv, fetchFromGitHub }:
  
  stdenv.mkDerivation rec {
    name = "tbb-${version}";
    version = "2018_U1";
  
  
negative.code:     rev = version;
      sha256 = "1lygz07va6hsv2vlx9zwz5d2n81rxsdhmh0pqxgj8n1bvb1rp0qw";
    };
  
    makeFlags = concatStringsSep " " (
      optional (compiler != null) "compiler=${compiler}" ++
      optional (stdver != null) "stdver=${stdver}"
    );
  
    installPhase = ''
      mkdir -p $out/{lib,share/doc}
  