anchor.diff:  , ncurses, libX11, libXt, libXpm, libXaw, libXext
   , libusb1, docbook_xml_dtd_412, docbook_xsl, bc
   , libxslt, xmlto, gpsdUser ? "gpsd", gpsdGroup ? "dialout"
  -, pythonPackages
  +, python2Packages
   }:
   
   # TODO: put the X11 deps behind a guiSupport parameter for headless support
  
positive.code:     sed -e "s|systemd_dir = .*|systemd_dir = '$out/lib/systemd/system'|" -i SConstruct
      scons prefix="$out" leapfetch=no gpsd_user=${gpsdUser} gpsd_group=${gpsdGroup} \
          systemd=yes udevdir="$out/lib/udev" \
          python_libdir="$out/lib/${pythonPackages.python.libPrefix}/site-packages"
    '';
  
    checkPhase = ''
  
negative.code: 
    nativeBuildInputs = [
      scons pkgconfig docbook_xml_dtd_412 docbook_xsl xmlto bc
      python2Packages.python
      python2Packages.wrapPython
    ];
  
    buildInputs = [
      python2Packages.python dbus dbus_glib ncurses libX11 libXt libXpm libXaw libXext
      libxslt libusb1
    ];
  
    pythonPath = [
      python2Packages.pygobject2
      python2Packages.pygtk
    ];
  
    patches = [
  