anchor.diff:      "-dbus-linked"
   
       "-system-sqlite"
  -    "-${if libmysql != null then "plugin" else "no"}-sql-mysql"
  +    "-${if mysql_lib != null then "plugin" else "no"}-sql-mysql"
       "-${if postgresql != null then "plugin" else "no"}-sql-psql"
   
       "-make" "libs"
  
positive.code: , xorg, libxkbcommon
  , fontconfig, freetype, openssl, dbus, glib, systemd_lib, libxml2, libxslt, pcre
  , zlib, libjpeg, libpng, libtiff, sqlite, icu, harfbuzz, libinput, mtdev
  
  , coreutils, bison, flex, gdb, gperf, ruby
  , python, perl, pkgconfig
  
  # optional dependencies
  , cups ? null
  , libmysql ? null, postgresql ? null
  
  # options
  , mesa
  
negative.code:     fontconfig freetype openssl dbus glib systemd_lib libxml2 libxslt pcre
      zlib libjpeg libpng libtiff sqlite icu harfbuzz libinput mtdev mesa
      xorg.xcbutil xorg.xcbutilimage xorg.xcbutilkeysyms xorg.xcbutilwm libxkbcommon
      xorg.inputproto xorg.xproto xorg.renderproto xorg.libXfixes xorg.fixesproto
      xorg.xcbutilrenderutil pulseaudio_lib alsa-lib
    ]
    ++ lib.optional (cups != null) cups
    ++ lib.optional (mysql_lib != null) mysql_lib
    ++ lib.optional (postgresql != null) postgresql
    ++ lib.optionals gtkStyle [gnome_vfs libgnomeui gtk2 GConf];
  
  