Your cameras become sensors for your whole home — Calyston + Home Assistant

Point Calyston at your MQTT broker — four fields, no YAML — and every camera shows up in Home Assistant as a device with motion, person, vehicle and animal sensors. Here's what appears, what you can build with it, and exactly how it works.

If you run Home Assistant, you've probably had this thought while adding yet another PIR sensor to a room: the camera in that corner can already see everything the sensor can — why doesn't it just tell my house?

Now it does. Calyston publishes everything it knows — motion, person, vehicle and animal detections, camera online/offline state, even the snapshot of the last detection — straight into Home Assistant. And you set it up with your mouse.

The whole setup, honestly

In Calyston → Settings, find the Home Assistant (MQTT) card. Enter your broker's address and credentials — four fields — and press Test connection.
That's it. There is no step 2.

Every camera you've added to Calyston appears in Home Assistant as its own device, automatically, within seconds:

a motion sensor (flips on the moment motion starts, off when it ends)
person / vehicle / animal sensors (from Calyston's AI detections, with a sensible auto-off)
an availability state — if the camera drops offline, or the Calyston box itself goes down, Home Assistant shows the entities as unavailable instead of silently lying to your automations with stale data
a camera entity holding the last detection snapshot — the actual frame that triggered the event

No YAML. Not on our side — the card in Settings is the entire configuration — and not on Home Assistant's side either: we use MQTT Discovery, so the devices register themselves. If you later rename a camera in Calyston, it renames itself in Home Assistant too.

The one prerequisite is an MQTT broker, which in the Home Assistant world you almost certainly have already — and if not, the Mosquitto add-on is a three-click install, also without YAML.

What you build with it

This is the part we're genuinely excited about, because it's the part we didn't have to build. Home Assistant is the best automation engine in the home, full stop. Our job is to be a high-quality signal source for it:

Person on the driveway after dark → porch and pathway lights on.
Vehicle detected at the gate → announcement on the kitchen speaker, with the snapshot on the wall tablet.
Motion in the living room while everyone's phones are away → siren, or a notification with the picture attached.
Any camera goes unavailable → you know within seconds, not when you check the footage three days later.

Combine our sensors with the ones you already own — door contacts, presence, lights, thermostats. Your cameras stop being a thing you look at and become sensors your whole home reacts to. You configure what's worth detecting in Calyston — cameras, categories, zones, all point-and-click — and Home Assistant decides what happens next.

How it works (for the technically curious)

Calyston keeps one persistent connection to your broker and publishes per-camera topics (calyston/<camera>/motion, /person, /availability, …) plus retained Home Assistant discovery configs. A few details we sweated so you don't have to:

Publish-only. Calyston subscribes to nothing but Home Assistant's status topic (to re-announce devices after an HA restart). There is no command channel — nothing on your MQTT bus can control or reconfigure your recorder.
Honest availability. We use an MQTT Last Will plus explicit retained offline messages on clean shutdown, so entities go unavailable whether Calyston dies suddenly or is stopped gracefully. We e2e-test both paths — including kill -9.
Fail-soft by design. If the broker is down, events are dropped and everything re-announces on reconnect. The bridge can never slow down or break recording and detection — those always come first.
Local, like everything else. Your broker, your network, your rules. No frame and no event leaves your LAN unless you forward it somewhere.

What it costs

The bridge is free on every tier, forever — including Community. What flows through it follows what your plan already does: motion and availability on Community; person, vehicle and animal sensors plus detection snapshots on plans with AI detection. No separate "integration" upsell — if Calyston detects it, Home Assistant gets it.

Your cameras already see everything. Now the rest of your home gets to know about it.