anchor.diff:    };
   
     go-log = buildFromGitHub {
  -    version = 2;
  +    version = 5;
       owner = "ipfs";
       repo = "go-log";
  -    date = "2017-03-16";
  -    rev = "48d644b006ba26f1793bffc46396e981801078e3";
  -    sha256 = "1s2kjgrg12r1lpickn8qxvi3642rf34i17gda3jwzwn2gp9jyyvr";
  +    date = "2017-12-28";
  +    rev = "e0fe369886faa4e8baa9d3630259821688fcb299";
  +    sha256 = "0c30q4npfnrwwjhfz8h4digqslp037a2b8g832r3bnv06d1d4l34";
       propagatedBuildInputs = [
         whyrusleeping_go-logging
  +      opentracing-go
       ];
     };
   
  
positive.code:   };
  
    go-resiliency = buildFromGitHub {
      version = 3;
      rev = "b1fe83b5b03f624450823b751b662259ffc6af70";
      owner  = "eapache";
      repo   = "go-resiliency";
      sha256 = "0iyn9ssm02ila0n8lm44awgsdpvzv833y0zwk9pgnm7s089slm8g";
      date = "2017-06-07";
    };
  
    go-restful = buildFromGitHub {
  
negative.code:   };
  
    go-tcp-transport = buildFromGitHub {
      version = 5;
      owner = "libp2p";
      repo = "go-tcp-transport";
      rev = "e80e6dde8a3d7e293bd52ff419ffb56f6c15dfe0";
      sha256 = "0laalwa7f76i9yl0n9gxicvp145w4m47v4lc979mfii8791mv645";
      date = "2017-12-28";
      propagatedBuildInputs = [
        go-log
        go-libp2p-transport
  