+1 for Home Assistant
I have it running on a Pi 5 (although a Pi 4 is more then enough), with a 15€ USB ZigBee antenna from AliExpress (to connect IKEA devices).
The best thing about it is that it seamlessly integrates all devices with each other, so you can use cheap ZigBee buttons to control your Philipps Hue lightbulbs, for example.
There’s a semantic difference between “supporting mods” and “provide support for modded installations”. The former is fairly common and is what steam workshop is about and is what you are talking about.
The latter is basically unheard of (for what I hope are obvious reasons).
The OP is a bit ambiguous about which of the two or is.