anchor.diff:  
     crypto = buildGoPackage rec {
       rev = "4d48e5fa3d62b5e6e71260571bf76c767198ca02";
  -    name = "go-crypto-${rev}";
  +    name = "crypto-${stdenv.lib.strings.substring 0 7 rev}";
       goPackagePath = "golang.org/x/crypto";
       goPackageAliases = [ "code.google.com/p/go.crypto" ];
       disabled = isGo13;
  
positive.code: 
  
    tools = buildGoPackage rec {
      rev = "140fcaadc5860b1a014ec69fdeec807fe3b787e8";
      name = "go.tools-${stdenv.lib.strings.substring 0 7 rev}";
      goPackagePath = "code.google.com/p/go.tools";
      src = fetchhg {
        inherit rev;
        url = "http://code.google.com/p/go.tools";
        sha256 = "1vgz4kxy0p56qh6pfbs2c68156hakgx4cmrci9jbg7lnrdaz4y56";
      };
      subPackages = [ "go/vcs" ];
    };
  
    ## THIRD PARTY
  
negative.code:       inherit rev;
        owner = "golang";
        repo = "net";
        sha256 = "1fk62vjxsyca8hmlpca9rkgy8wqg9zw920d56ib442sjn9ys3zic";
      };
  
      propagatedBuildInputs = [ text ];
  