AlertU

How it works

Six steps, one reflex

The same loop a car alarm runs — arm, watch, react — living quietly in a daemon on your machine.

ArmOne click locks the session.
LeaveGrab a coffee. The watch goes live.
DetectA touched key or mouse trips it.
AlarmA countdown, then the siren.
SnapshotThe webcam saves a still.
DisarmClick again — back to calm.

Intrusion

It knows the moment someone touches it

Once armed, AlertU watches your input devices at the kernel level. A nudge of the mouse, a tap on the keyboard, a brush of the trackpad — anything on a watched device starts an adjustable countdown, with a discreet warning tick.

Watches any input device — keyboard, mouse, trackpad
A grace period after arming, so you can walk away clean
X11 or Wayland — it only talks to logind

Alarm

Then it makes noise

When the countdown runs out, the siren loops and the machine stops being subtle. Wire the optional webhook to your phone, Slack or Discord and the alert lands in your pocket, wherever you are.

A looping siren, loud enough to turn heads
An optional webhook — send it to your phone, your way

Evidence

And remembers the face

The instant the alarm fires, AlertU saves a timestamped still from the webcam. Come back to a small gallery of exactly who leaned in while you were gone.

Timestamped stills, saved locally
Kept private — mode 0640, never world-readable

Disarm

Stand down the way you armed it

Your remote is the key fob. A second click, or a normal password unlock, drops everything straight back to calm. Whichever comes first wins — unlock during the countdown and nothing ever fires.

Any USB or Bluetooth remote becomes the fob
Or just unlock the screen — logind tells AlertU in real time

Built for developers

Small, local, and honest about it

No cloud, no account, no telemetry. Four tiny binaries talking over one local socket.

Any Linux desktop

X11 and Wayland, any distro with systemd. No desktop environment required.

Open source

MIT licensed, built in the open. Read every line, send a patch.

Privacy first

Everything stays on your machine. The only thing that leaves is the webhook you set.

Fast setup

One package for your distro, name your remote, and you are armed in a minute.

Lightweight

Pure Rust where it counts. No GTK, no Qt, no ALSA linkage.

Tested to the core

102 tests on every push, with rustfmt and clippy at -D warnings.

In practice

A coffee break, guarded

The whole story, the way it actually plays out.

You kick off a long compile.
You arm AlertU and stand up.
Someone touches your keyboard.
The siren goes off.
A snapshot is captured.
You click your remote — calm again.

Install

A package for your distribution

Every release ships an .rpm and a .deb — all four binaries, the systemd units and the sounds. On any other distro, build it with cargo.

Fedorasudo dnf install ./alertu-*.rpm

Debian · Ubuntusudo apt install ./alertu_*.deb

Sourcecargo build --release

A package cannot add you to a group or start a user unit, so a couple of lines are yours. Full walkthrough in the README.

alertu-ctl

$ alertu-ctl status
Idle
$ alertu-ctl toggle
ok
$ alertu-ctl --json status --watch
{"event":"state","state":"armed"}
{"event":"state_changed","state":"triggered"}
{"event":"state_changed","state":"alarm"}