Your automatic garage door is almost certainly the most vulnerable access point in your house. Traditional systems are notorious for their susceptibility to replay attacks, but even more sophisticated modern garage door openers and those that lack remote functionality entirely are still prone to human error — you may simply forget to close the door. This “auto closer” system developed by SébastienL42 prevents such errors.

At its heart, this setup’s purpose is to close a garage door that a homeowner mistakenly left open. That’s a common problem, as you can see for yourself if you drive around a suburban residential neighborhood at night. If a homeowner forgets to close their garage door, SébastienL42’s device will sound a notification through an indoor dashboard. If enough time passes, it will go ahead and close the door itself.

That functionality requires two Arduino Nano Every boards. The first goes in the garage and connects to the garage door opener so it can close to the door. It detects a closed door using a pair of microswitches. The second Arduino is for the indoor dashboard, which provides notifications and control buttons. SébastienL42 designed that dashboard to fit into a picture frame and it looks really nice.

The two Arduino boards communicate with each other via nRF24L01 radio transceiver modules, which could potentially create a new vulnerability. But SébastienL42 put serious thought into that possibility and eliminated exposure by simply making the system incapable of opening the garage door — it can only close it. If a bad actor somehow gained access, they wouldn’t be able to do anything more nefarious than close the door for the homeowner. And the garage door opener’s standard safety features remain in place, so there shouldn’t be any danger.