anchor.diff:  with stdenv.lib;
   let
     copts = concatStringsSep " " ([
  -    "-DHAVE_DBUS"
       "-DHAVE_IDN"
       "-DHAVE_DNSSEC"
     ] ++ optionals stdenv.isLinux [
  +    "-DHAVE_DBUS"
       "-DHAVE_CONNTRACK"
     ]);
   in
  
positive.code:   '';
  
    nativeBuildInputs = [ pkgconfig ];
    buildInputs = [ dbus_libs nettle libidn ]
      ++ optional stdenv.isLinux libnetfilter_conntrack;
  
    meta = {
      description = "An integrated DNS, DHCP and TFTP server for small networks";
  
negative.code:     "LOCALEDIR=$(out)/share/locale"
    ];
  
    postBuild = optionalString stdenv.isLinux ''
      make -C contrib/wrt
    '';
  
    # XXX: Does the systemd service definition really belong here when our NixOS
    # module can create it in Nix-land?
    postInstall = ''
      install -Dm644 trust-anchors.conf $out/share/dnsmasq/trust-anchors.conf
    '' + optionalString stdenv.isLinux ''
      install -Dm644 dbus/dnsmasq.conf $out/etc/dbus-1/system.d/dnsmasq.conf
      install -Dm755 contrib/wrt/dhcp_lease_time $out/bin/dhcp_lease_time
      install -Dm755 contrib/wrt/dhcp_release $out/bin/dhcp_release
  
  