anchor.diff:        sys
       ];
       meta.useUnstable = true;
  -    date = "2018-03-29";
  +    date = "2018-05-23";
     };
   
     logutils = buildFromGitHub {
  
positive.code: 
    demangle = buildFromGitHub {
      version = 6;
      date = "2016-09-27";
      rev = "4883227f66371e02c4948937d3e2be1664d9be38";
      owner = "ianlancetaylor";
      repo = "demangle";
      sha256 = "09rsl8cgn9jgdi2s2vhji92mzy6qirbvg2j74nhq3x0y5pk0s08c";
    };
  
    dexlogconfig = buildFromGitHub {
  
negative.code: 
    siddontang_go = buildFromGitHub {
      version = 6;
      date = "2018-05-14";
      rev = "2b7082d296ba89ae7ead0f977816bddefb65df9d";
      owner = "siddontang";
      repo = "go";
      sha256 = "136m4ly711i9mmwkfqf3wqijgqg16sz37kr5ia6fqwsn87cp6fwk";
    };
  
    ugorji_go = buildFromGitHub {
  