anchor.diff:  { stdenv, fetchurl }:
   
   stdenv.mkDerivation {
  -  name = "tbb-4.0-u5";
  +  name = "tbb-4.2-u5";
   
     src = fetchurl {
  -    url = "http://threadingbuildingblocks.org/uploads/77/187/4.0%20update%205/tbb40_20120613oss_src.tgz";
  -    sha256 = "aaa98146049e55f6ac969298340eeb49df61395403fcc1480824a4ecd0d46192";
  +    url = "https://www.threadingbuildingblocks.org/sites/default/files/software_releases/source/tbb42_20140601oss_src.tgz";
  +    sha256 = "1zjh81hvfxvk1v1li27w1nm3bp6kqv913lxfb2pqa134dibw2pp7";
     };
   
     checkTarget = "test";
  
positive.code:       represents a higher-level, task-based parallelism that abstracts platform
        details and threading mechanisms for scalability and performance.
      '';
  
      maintainers = [ stdenv.lib.maintainers.simons ];
      platforms = stdenv.lib.platforms.linux;
    };
  }
  
negative.code:   enableParallelBuilding = true;
  
    meta = {
      description = "Intel Thread Building Blocks C++ Library";
      homepage = "http://threadingbuildingblocks.org/";
      license = "LGPLv3+";
      longDescription = ''
        Intel Threading Building Blocks offers a rich and complete approach to
        expressing parallelism in a C++ program. It is a library that helps you
  