I recently integrated my bathroom ventilation system with Home Assistant, and it’s been a fantastic experience! Using a Perilex-controlled exhaust unit connected via a Shelly 2.5, I’ve managed to automate the fan speed based on humidity levels. This not only reduces noise during daily activities but also ensures efficient ventilation when needed. 
I documented the entire process, including Arduino code and automation examples, in a blog post. It’s been a great way to save energy and improve comfort in my home. If anyone has questions or wants to share their own smart home projects, I’d love to hear about them!