libevdev_uinput_create_from_device failed: No such file or directory

I tried on Arch Linux using the AUR package and it runs flawlessly. On Gentoo however, putting the 4 executables in my PATH, it fails:

# udevmon -c ~/temp/interception/config.yaml
libevdev_uinput_create_from_device failed: No such file or directory

With config.yaml as per the README:

- JOB: "intercept -g $DEVNODE | caps2esc | uinput -d $DEVNODE"
  DEVICE:
    EVENTS:
      EV_KEY: [KEY_CAPSLOCK, KEY_ESC]

I tried replacing $DEVNODE with the actual /dev/ path to my keyboard, to no avail.