anchor.diff:  
   buildGoPackage rec {
     name = "prometheus-${version}";
  -  version = "1.4.1";
  +  version = "1.5.2";
     rev = "v${version}";
   
     goPackagePath = "github.com/prometheus/prometheus";
  
positive.code:     description = "Service monitoring system and time series database";
      homepage = http://prometheus.io;
      license = licenses.asl20;
      maintainers = with maintainers; [ benley ];
      platforms = platforms.unix;
    };
  }
  
negative.code:     inherit rev;
      owner = "prometheus";
      repo = "prometheus";
      sha256 = "1b24nx6gmx2c7fj92p2byla3i0zs6xwymxqji00gvgpxr8bsfhn1";
    };
  
    docheck = true;
  