anchor.diff:  
   with {
     inherit (stdenv.lib)
  -    optionals;
  +    optionals
  +    wtFlag;
   };
   
   stdenv.mkDerivation rec {
  
positive.code:     rev = "62cb5a4605c0664bc522e0e0da9c72f09cf643a9";
      sha256 = "0l2kqkbfl5l7drmqdqdryq1p0fpz05aghxrqd29fs4j9bx0djnaw";
    };
  
    patches = optionals colorSupport [
      # Optional patch adds support for custom configurable colors
  
negative.code:     "--enable-largefile"
      "--with-statvfs"
      "--with-statfs"
      (wtFlag "ncurses" (ncurses != null) null)
      (wtFlag "ncursesw" (ncurses != null) null)
      (wtFlag "xmlrpc-c" (xmlrpc_c != null) null)
    ];
  
    postInstall = ''
      mkdir -pv $out/share/rtorrent
      mv -v doc/rtorrent.rc $out/share/rtorrent/rtorrent.rc
    '';
  
    meta = with stdenv.lib; {
      description = "An ncurses client for libtorrent";
  