Native macOS app · macOS 14+
Mona Lisa is a lightweight menu-bar agent that checks who is sitting at your Mac. If it can't verify an enrolled face, it locks every screen and records whoever's there — until your password is entered (or a trusted face is). The lock survives a reboot.
downloads
Requires macOS 14 Sonoma or later and a camera. Apple Silicon & Intel.
Grab MonaLisa.dmg, open it, and drag Mona Lisa onto the Applications shortcut.
Mona Lisa is distributed independently — not through the App Store — so macOS asks you to confirm the very first time you open it. This is normal for indie apps, and you only do it once:
After that, it launches normally like any other app.
Click the shield in the menu bar: Add a Person to enroll your face (grant camera access when asked), set an unlock password in Settings, then hit Start Monitoring. Done — it auto-starts at login from now on.
Three moving parts, all native macOS. No accounts, no cloud, no agents phoning home.
A live preview guides you through five head positions — front, both sides, up, and down — capturing 15 samples so the face is recognized from every angle, and auto-calibrates a match threshold. Add as many people as you like and remove them any time.
Every 30 seconds (you choose), it wakes the camera for a single frame, runs Apple's Vision framework on-device, and goes back to sleep. The camera light just blinks — and between checks the app sits at ~0% CPU.
The moment it's sure an unrecognized person is using the Mac, it drops a full-screen lock over every display and records video of the whole locked period. It disables force-quit and app switching, re-applies itself after a reboot, and unlocks with your password — or a trusted face passing a blink check.
A deterrent against opportunistic use, not full-disk encryption — pair it with FileVault for real theft protection.
Keep scrolling — glide through the releases, newest to oldest.
kill / killall can no longer silently stop protection — it goes through the same password / blink check as Pause and Quit