anchor.diff:  
     tools = buildFromGitHub {
       version = 2;
  -    rev = "d63e2b22b05a9682de336cd4802bba367ed429e7";
  -    date = "2017-03-28";
  +    rev = "37a1062ad0bb70f026cd45d6b92cb37eacd927bb";
  +    date = "2017-04-03";
       owner = "golang";
       repo = "tools";
  -    sha256 = "1nv86pi5iin5ak2kq1x8hwk0d284qqk03zgbmi9kh081id50yzlb";
  +    sha256 = "0mj2gjbz495vq05v5sq3mm9nj93qq8xc9n86cbfc0c7xr6mrxmj6";
       goPackagePath = "golang.org/x/tools";
       goPackageAliases = [ "code.google.com/p/go.tools" ];
   
  
positive.code:     version = 2;
      owner = "minio";
      repo = "minio-go";
      rev = "52e12c8b9889bfaaa2cf464c68d8933e380e30ed";
      sha256 = "1j6ihhzic6b37j1rwfr8b88vslf20q8jwmsy5w40zi0d1m98wga3";
      meta.useUnstable = true;
      date = "2017-03-30";
    };
  
    missinggo = buildFromGitHub {
  
negative.code: 
    go-getter = buildFromGitHub {
      version = 2;
      rev = "615ccd8621bdb3837e18be586ce15655ef52b185";
      date = "2017-04-04";
      owner = "hashicorp";
      repo = "go-getter";
      sha256 = "1bc65z7iw238smscic97vhyrq2nlily60lgp24z62z5cfj0aax53";
      propagatedBuildInputs = [
        aws-sdk-go
        go-homedir
  