anchor.diff:  
     go-floodsub = buildFromGitHub {
       version = 2;
  -    rev = "a5b52ed01372e8223f3ebb8e2da81b07e6105226";
  +    rev = "98a3f2b40c27a350c799217c028b006215bc9d45";
       owner  = "libp2p";
       repo   = "go-floodsub";
  -    sha256 = "1frvaxqs57lwnjsicsr008nhdwpblmxcivq0n329ywbfj8m62z01";
  -    date = "2017-01-06";
  +    sha256 = "1b9sfvvl16qbrcjysi7r6xlg9nnc0gwhvw5z4phlpjcb78fap74l";
  +    date = "2017-01-10";
       propagatedBuildInputs = [
         gogo_protobuf
         go-libp2p-host
  
positive.code: 
    tools = buildFromGitHub {
      version = 2;
      rev = "354f9f8b43608012e8192f2e8d9e13c615df5c34";
      date = "2017-01-07";
      owner = "golang";
      repo = "tools";
      sha256 = "1qimmap3f1rhclsy549gr44n0dns4jpp65797yvb4c68wy29y90l";
      goPackagePath = "golang.org/x/tools";
      goPackageAliases = [ "code.google.com/p/go.tools" ];
  
  
negative.code:       profile
        structs
      ];
      date = "2017-01-10";
    };
  
    mdns = buildFromGitHub {
  