anchor.diff:  { stdenv, fetchurl, libX11, inputproto, libXt, libXpm, libXft, fontconfig
  -, libXtst, xextproto, readline, libXi, pkgconfig, autoconf, automake }:
  +, libXtst, xextproto, readline, libXi, pkgconfig, perl, autoconf, automake }:
   
   stdenv.mkDerivation rec {
     name = "ratpoison-1.4.5";
  
positive.code:        })
      ];
  
    preConfigure = "autoreconf -vf";
  
    buildInputs =
      [ libX11 inputproto libXt
        libXpm libXft fontconfig libXtst
        xextproto readline libXi pkgconfig
        autoconf automake  # needed because of the patch above
      ];
  
    meta = {
  
negative.code: 
      homepage = http://www.nongnu.org/ratpoison/;
  
      maintainers = [ stdenv.lib.maintainers.ludo stdenv.lib.maintainers.simons ];
      platforms = stdenv.lib.platforms.gnu;  # arbitrary choice
    };
  }
  