kinda works now...! ( i didn't install phase, just make and make installed)

qlcplus.nix

{ stdenv, fetchurl, pkgconfig, ccache, makeWrapper, qmake4Hook, qt4, libftdi1, alsaLib, libudev, libusb}:

stdenv.mkDerivation rec {
  name = "qlcplus-${version}";
  version = "4.10.3";

  src = fetchurl {
    url = "http://www.qlcplus.org/downloads/${version}/qlcplus_${version}.tar.gz";
    sha256 = "1mrhlqvbgs8qnj7qik70a3gywvmck1malygqi0hm403j5w6f2bgb";
  };

  buildInputs = [ ccache libudev pkgconfig libftdi1 qmake4Hook makeWrapper qt4 alsaLib libusb ];

  qmakeFlags = [ 
    "QMAKE_CXXFLAGS+=-Wno-error=unused-variable"
  ];
  
  installFlags = [ "INSTALL_ROOT=$(out)" ];

  postFixup= ''
    wrapProgram $out/usr/bin/qlcplus \
      --prefix QT_PLUGIN_PATH : $out/usr/lib/qt4/plugins \
      --prefix LD_LIBRARY_PATH : $out/usr/lib
  '';

  meta = {
    description = "The open DMX lighting desk software for controlling professional lighting fixtures";
    homepage = http://www.qlcplus.org;
    license = stdenv.lib.licenses.asl20;
    maintainers = with stdenv.lib.maintainers; [ sleexyz ];
    platforms = with stdenv.lib.platforms; linux;
  };
}