anchor.diff: -{ stdenv, fetchurl, ghc, perl, gmp, ncurses, libiconv }:
  +{ stdenv, fetchurl, fetchpatch, ghc, perl, gmp, ncurses, libiconv }:
   
   let
   
  
positive.code:       libraries/base_CONFIGURE_OPTS += --configure-option=--with-iconv-libraries="${libiconv}/lib"
      ''}
    '';
  
  in
  
  
negative.code: 
    enableParallelBuilding = true;
  
    postPatch = ''
      pushd libraries/Cabal
      patch -p1 < ${cabalPatch}
      popd
    '';
  
    preConfigure = ''
      echo >mk/build.mk "${buildMK}"
      sed -i -e 's|-isysroot /Developer/SDKs/MacOSX10.5.sdk||' configure
    '' + stdenv.lib.optionalString (!stdenv.isDarwin) ''
  