It's pretty awesome, actually. Most stuff in my house is gear that's been re-flashed to Tasmota, and for a decent period of time the "CE Smart" (plugs , outlets, dimmers, bulbs) branded stuff used Tuya chips which were pretty easy to flash. Costco sold these, but the guts have changed over time.

The older Tuya based stuff can be flashed OTA to Tasmota using a raspberry Pi and a special app, but meant of the newer ones use a different chipset that is no longer compatible (or at least last time I gave it a shot). Much newer stuff seems to have crappy realtek chips that won't take Tasmota, though I haven't picked up anything recently. Devices that still use an ESP82xx chipset were also flashable by serial connection soldered to the right leads (RX,TX,3.3v, ground and NO AC power).

About a year ago, HomeAssistant stopped working with straight MQTT based Tasmota after a certain version. Thankfully, there's actually a native Tasmota plugin now that actually works better for hardware running that particular variety of open-source firmware, and it's actually become a bit easier to use.

If anyone snags a compatible "CE Smart" dimmer and manages to flash it, I've still got a functional template and the command that makes it work nicely in dimmer mode.

My current project is actually to reflash a sonoff ceiling fan controller and get that integrated.