anchor.diff:  
   let self = dotnetPackages // overrides; dotnetPackages = with self; {
   
  +  # BINARY PACKAGES
  +
     Autofac = fetchNuGet {
       baseName = "Autofac";
       version = "3.5.2";
  
positive.code:     outputFiles = [ "lib/net40/*" ];
    };
  
    FsCheck = fetchNuGet {
      baseName = "FsCheck";
      version = "1.0.4";
  
negative.code:       platforms = with stdenv.lib.platforms; linux;
      };
    };
  
  }; in self
  