The best devices have a local web interface so you can control them with your computer (like how you control your router).

Unfortunately, almost no lan connected devices sport such an interface.

There’s a pretty active ecosystem of ESP32 projects for HVAC systems. I’ve been working on a few that add Apple Home and Matter support with a local web interface for basic and advanced features. The web interface exposes things Apple Home or Matter protocols don’t represent well. Vane positions, different modes (dry, fan only), equipment diagnostics, remote sensor control, and even peer to peer communication for fully offline control (no WiFi needed). Plus it gets me a control path independent of the home automation stack. There’s a lot you can put on the device itself these days.

With another project, based on the ESP32-S3, I was able to cram grafana style scrubbable charts, full activity log, refrigerant circuit diagram, equipment topology, etc. I'm pretty excited for the ESP32-S31 since it's a nice jump up in performance.

I tried to stick to this philosophy, specifically the part about it working even if my local automation server is down, for a long time. But I finally found an automation case where I wanted functionality where I could not simultaneously have the functionality and have the switch continue working when the server was off.

Specifically, I wanted the switch to turn on different lights depending on the time of day. In the evenings in early morning I wanted it to turn on the dimmer floor lamps, and during the day, I wanted it to turn on the brighter Center room light. This was not possible without turning the switch from a light turning on device, to an automation activating device.

I thought really long and hard about if I was worth the trade off, and in the end I decided that my automation server was only likely to be down for significant periods of time if the power was out and the lights weren't working anyways. If I run into a situation where this becomes a problem for me, I'll reconsider my decision. Which is a great thing about the local control. If I make a decision that I don't like I can just change it.

> 1. No network, no problem. Anything core to the house has to work with Wi-Fi or automation server shut down.

This is one of the reasons I love Zigbee, the device network is entirely independent of my computer network, can not directly communicate to the internet in any way, and every device I've put on the network so far can be configured to directly communicate with other devices so basic functionality remains operational even if the controller goes down.

For example, in my living room I have a Lutron Aurora dimmer dial locking a standard switch in the on position, then plugged in to the outlet that switch would normally control is a Leviton dimmer module. Both connect to the network controlled from a PoE Zigbee dongle, but have been directly paired as well so pressing the button on the dial makes it directly tell the dimmer module to turn on, rotation commands are sent direct, etc.

The controller also receives these commands when it's active and can add to the functionality for inputs like double-click, but if it's down the basic functionality still works entirely as a normal person would expect. You walk in to the room and see a knob on a switch plate, you turn the knob and the light brightness increases regardless of the state of the internet, my home server, or even my network as a whole.

The other major advantage compared to Matter/Thread is that it's not IP based so it's impossible for any Zigbee device to ever have a cloud dependency. No matter how much some marketing dingus might want to, it can not be ruined.