anchor.diff:      owner = "spacemonkeygo";
       repo = "spacelog";
       sha256 = "0rsg4z5lci3fiyby1abh0xai6k25h83r1k94yiwjgmq9fwcfbcbc";
  -    buildInputs = [ flagfile ];
  +    buildInputs = [
  +      flagfile
  +      sys
  +    ];
     };
   
     spdystream = buildFromGitHub {
  
positive.code:     version = 3;
      owner = "Azure";
      repo = "go-ansiterm";
      rev = "19f72df4d05d31cbe1c56bfc8045c96babff6c7e";
      date = "2017-06-29";
      sha256 = "1lnv52868v32djwcl2xfhl8pawnq4hxlzaywlxfyr2yihc7d9vkm";
      buildInputs = [
        logrus
      ];
  
negative.code: 
    termbox-go = buildFromGitHub {
      version = 3;
      rev = "d51f2f6d6ccb97dd83ed04ae2f79c34234851f39";
      date = "2017-09-30";
      owner = "nsf";
      repo = "termbox-go";
      sha256 = "0b866s59zkp8r75msqi8hl2bjpjypxbzb2b4hm18w3vzj7hm4rc2";
      propagatedBuildInputs = [
        go-runewidth
      ];
  