anchor.diff: -{ stdenv, lib, fetchurl, ncurses, xlibsWrapper, libXaw, libXpm, Xaw3d
  +{ stdenv, lib, fetchurl, ncurses, xlibsWrapper, libXaw, libXpm, Xaw3d, fetchpatch
   , pkgconfig, gettext, libXft, dbus, libpng, libjpeg, libungif
   , libtiff, librsvg, gconf, libxml2, imagemagick, gnutls, libselinux
   , alsaLib, cairo, acl, gpm, AppKit, GSS, ImageIO
   , withX ? !stdenv.isDarwin
   , withGTK2 ? false, gtk2 ? null
   , withGTK3 ? true, gtk3 ? null, gsettings-desktop-schemas ? null
  -, withXwidgets ? false, webkitgtk24x-gtk3 ? null, wrapGAppsHook ? null, glib-networking ? null
  +, withXwidgets ? false, webkitgtk, wrapGAppsHook ? null, glib-networking ? null
   , withCsrc ? true
  -, srcRepo ? false, autoconf ? null, automake ? null, texinfo ? null
  +, autoconf ? null, automake ? null, texinfo ? null
   }:
   
   assert (libXft != null) -> libpng != null;      # probably a bug
  
positive.code:       url = "https://gist.githubusercontent.com/aaronjensen/f45894ddf431ecbff78b1bcf533d3e6b/raw/6a5cd7f57341aba673234348d8b0d2e776f86719/Emacs-25-OS-X-use-vfork.patch";
        sha256 = "1nlsxiaynswqhy99jf4mw9x0sndhwcrwy8713kq1l3xqv9dbrzgj";
      })
    ];
  
    nativeBuildInputs = [ pkgconfig ]
      ++ lib.optionals srcRepo [ autoconf automake texinfo ]
      ++ lib.optional (withX && (withGTK3 || withXwidgets)) wrapGAppsHook;
  
    buildInputs =
  
negative.code:              "--with-gif=no" "--with-tiff=no" ])
      ++ lib.optional withXwidgets "--with-xwidgets";
  
    preConfigure = ''
      ./autogen.sh
    '' + ''
      substituteInPlace lisp/international/mule-cmds.el \
  