anchor.diff:  
     unpackPhase = ''
       sh $src --keep --noexec
  +    cd pkg/run_files
  +    sh cuda-linux64-rel-5.5.22-16488124.run --keep --noexec
       cd pkg
     '';
   
  
positive.code:   src =
      if stdenv.system == "x86_64-linux" then
        fetchurl {
          url = http://developer.download.nvidia.com/compute/cuda/4_2/rel/toolkit/cudatoolkit_4.2.9_linux_64_suse11.2.run;
          sha256 = "1inngzwq520bhpdfrh5bm4cxfyf3hxj94jialjxgviri5bj9hz60";
        }
      else throw "cudatoolkit does not support platform ${stdenv.system}";
  
  
negative.code: } :
  
  stdenv.mkDerivation rec {
    name = "cudatoolkit-5.5.22";
  
    dontPatchELF = true;
    dontStrip = true;
  