anchor.diff:    ];
   
     configureFlags = [
  -    "--disable-maintainer-mode"
       "--enable-udev"
  -    "--disable-usbdk"
  -    #"--enable-timerfd"
  -    "--enable-log"
  -    "--disable-debug-log"
  -    "--enable-system-log"
  -    "--disable-examples-build"
  -    "--disable-tests-build"
  +    "--enable-timerfd"
     ];
   
     NIX_LDFLAGS = [
  
positive.code:   inherit (stdenv.lib)
      optional;
  
    version = "1.0.21";
  in
  stdenv.mkDerivation rec {
    name = "libusb-${version}";
  
negative.code:   src = fetchurl {
      url = "https://github.com/libusb/libusb/releases/download/v${version}/"
        + "${name}.tar.bz2";
      sha256 = "75aeb9d59a4fdb800d329a545c2e6799f732362193b465ea198f2aa275518157";
    };
  
    buildInputs = [
  