anchor.diff:        ln -sv $(cd $out/bin && echo qemu-system-*) $out/bin/qemu-kvm
       '';
   
  +  enableParallelBuilding = true;
  +
     meta = {
       homepage = http://www.linux-kvm.org/;
       description = "A full virtualization solution for Linux on x86 hardware containing virtualization extensions";
  
positive.code:   configureFlags =
      [ "--audio-drv-list=alsa"
        "--smbd=smbd"                               # use `smbd' from $PATH
      ] ++ stdenv.lib.optional spiceSupport "--enable-spice";
  
    enableParallelBuilding = true;
  
    buildInputs =
      [ attr zlib SDL alsaLib pkgconfig pciutils libuuid vde2 libjpeg libpng
        ncurses python glib libaio mesa
      ] ++ stdenv.lib.optionals spiceSupport [ spice_protocol spice ];
  
    postInstall =
      ''
  
negative.code: { stdenv, fetchurl, attr, zlib, SDL, alsaLib, pkgconfig, pciutils, libuuid, vde2
  , libjpeg, libpng, ncurses, python, glib, libaio, mesa, perl, texinfo
  , spice, spice_protocol, spiceSupport ? false }:
  
  assert stdenv.isLinux;
  