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: 
    sys = buildFromGitHub {
      version = 2;
      rev = "30de6d19a3bd89a5f38ae4028e23aaa5582648af";
      date = "2016-09-07";
      owner  = "golang";
      repo   = "sys";
      sha256 = "1a1j8cycykcd91h22rp0bk6zjy9nln2qpxiggpjcpd3szl9k99zv";
      goPackagePath = "golang.org/x/sys";
      goPackageAliases = [
        "github.com/golang/sys"
  
negative.code: 
    rcrowley_go-metrics = buildFromGitHub {
      version = 2;
      rev = "ab2277b1c5d15c3cba104e9cbddbdfc622df5ad8";
      date = "2016-09-21";
      owner = "rcrowley";
      repo = "go-metrics";
      sha256 = "0y51jzdnvpl0iab7wqvbrkw6wnrygkfcikfwwh95pnik7m6rwlnx";
      propagatedBuildInputs = [ stathat ];
    };
  
  