anchor.diff:  
       buildInputs = [
         datadog-go circbuf armon_go-metrics go-radix bolt go-dockerclient errwrap
  -      go-checkpoint go-cleanhttp go-immutable-radix go-memdb ugorji.go
  +      go-checkpoint go-cleanhttp go-immutable-radix go-memdb ugorji_go
         go-multierror go-syslog golang-lru hcl logutils memberlist
         net-rpc-msgpackrpc raft raft-boltdb scada-client serf yamux
         muxado dns cli mapstructure columnize crypto
  
positive.code:     owner = "hashicorp";
      repo = "net-rpc-msgpackrpc";
      sha256 = "0sqx6zw211fjphj1j6w7bc5191csh2jn1wkihycsd4mk5kbwvjxp";
      propagatedBuildInputs = [ ugorji.go go-multierror ];
    };
  
    ngrok = buildFromGitHub {
  
negative.code:     sha256 = "1gvgkx7llklz6plapb95fcql7d34i6j7anlvksqhdirpja465jnm";
    };
  
    ugorji_go = buildFromGitHub {
      date = "2015-12-01";
      rev = "357a44b2b13e2711a45e30016508134101477610";
      owner = "ugorji";
  