Is a hub needed for the system to work?

Hello, I’m new using Simple, I have a doubt can work everything correctly without using a hub? I hope someone can clarify my doubt, greetings

you can use an appletv 4 as a hub, or any dedicated apple device

Roomie v6.0+ does not require a hub. In 6.0+ the concept of a hub is replaced by the concept of a “controller.” Any device can be a controller and the system will automatically elect one device to be the controller. It is possible to have a primary or preferred controller, but it is not strictly required. The system is much more flexible now. I still prefer having a primary dedicated controller, but this is personal OCD preference.