anchor.diff:  
     syncthing = buildFromGitHub rec {
       version = 2;
  -    rev = "v0.14.6";
  +    rev = "v0.14.7";
       owner = "syncthing";
       repo = "syncthing";
  -    sha256 = "0nba0ddkc7zdqaw5gyhy1s0bdvd3ghsfvxc732v1m144w074z8yq";
  +    sha256 = "1ns9dv9xbmgnw97cc7am3fb4rg8zn2cgzp45l3ax1ffrrx0fcfgn";
       buildFlags = [ "-tags noupgrade" ];
       buildInputs = [
         go-lz4 du luhn xdr snappy ratelimit osext
         goleveldb suture qart crypto net text rcrowley_go-metrics
         go-nat-pmp glob gateway ql groupcache pq protobuf_gogo
  -      geoip2-golang
  +      geoip2-golang sha256-simd
       ];
       postPatch = ''
         # Mostly a cosmetic change
  
positive.code: 
    go4 = buildFromGitHub {
      version = 2;
      date = "2016-09-11";
      rev = "e7a2449258501866491620d4f47472e6100ca551";
      owner = "camlistore";
      repo = "go4";
      sha256 = "097ll3m8wbcr5ivcfwa47khw721sj4sd1fqkzyl1iwviyw8ycssd";
      goPackagePath = "go4.org";
      goPackageAliases = [ "github.com/camlistore/go4" ];
      buildInputs = [
  
negative.code: 
    sys = buildFromGitHub {
      version = 2;
      rev = "8f0908ab3b2457e2e15403d3697c9ef5cb4b57a9";
      date = "2016-09-14";
      owner  = "golang";
      repo   = "sys";
      sha256 = "0kk2za4grwh0kr6v5mvnr90pilqbp1x0rbrnfyz02y5p5blprhyl";
      goPackagePath = "golang.org/x/sys";
      goPackageAliases = [
        "github.com/golang/sys"
  