You can use home assistant and HomeKit together pretty seamlessly. We have all our lighting automation as a zwave network though hass, and the lights are also

You can use home assistant and HomeKit together pretty seamlessly. We have all our lighting automation as a zwave network though hass, and the lights are also included in HomeKit. We can use Siri or hass app or the native home app/widgets in iOS without any issues. And everything runs locally too.