Fully local solution with no 3rd party clouds, EULAs, proprietary hubs or propruetary apps or restrictions. Compatible with almost any zigbee device. A subset of tested and well-known devices is listed at their website https://www.zigbee2mqtt.io/supported-devices/.
Recommending to everyone. It can be set up as 3 docker containers (zigbee2mqtt, mosquitto, home assistant), for example in docker compose. Or there are also ready-made images of Home Assistant with Supervisor GUI management for people not wanting to fiddle with that manually.
Node-Red is another great addon to the setup if you want to configure automations graphically by joining nodes together. Far more powerful than any proprietary solutions.