Dozens!
(They also last longer than the premade stuff, including the fairly dumb zigbee devices. Though just grabbing some ZigBee sensors is soooo much easier than cleaning up and painting small 3d printed housings…)
They also last longer than the premade stuff,
And they’re a much nicer experience. It’s funny how fast even minimum hardware performs when it’s doing what I ask it to, instead of spying on me.
How do you learn? I have some ESP32s that I’ve messed around a little bit with, and done some neat stuff…But I don’t have an electronics background at all and I often have trouble even figuring out how to power the damn things safely.
Using homeassistant and esphome is a good starting place unless you want to learn python or C