How I Built a GNOME Utility to Disable My Laptop Keyboard (and What I Learned About Linux Input Devices)

Description and use

KeyFlip automatically disables a laptop’s built‑in keyboard when an external keyboard is connected, using udev hotplug events and fail‑open safety.

When using an external keyboard with a laptop, accidental typing on the built‑in keyboard drains productivity and can lock users out of input.

KeyFlip reliably disables the laptop keyboard when an external keyboard is connected, prevents accidental lockout, and runs with minimal overhead.

Detect built‑in keyboard via bus type and physical path
Subscribe to udev hotplug events for real‑time device changes
On external keyboard connect: disable built‑in keyboard if detection is confident
On disconnect: immediately re‑enable built‑in keyboard
Provide tray icon for manual override and status display

KeyFlip identifies the internal keyboard by its bus type and physical path…

The result: near‑instant response when you plug in or unplug a keyboard, with essentially no idle overhead.