I made a simple lock sensor with Xiaomi Door Sensor, some battery holders and a soldering iron

[chairstacker]

Here are a few more ideas in a thread that I started a little while ago:

How I made my dumb locks a little smarter!

All I wanted to achieve was to see in my HomeAssistant dashboard if the deadbolts on four doors (front, balcony, office, patio) were locked at the end of the day - and trigger some automation when I go to bed, e.g. tell me which deadbolt isn’t locked when I check if the house is ready for the night… For a while, I was looking into buying a smart look (or better: 4) to be able to see the status in Home Assistant, but couldn’t get myself to go that route because: I only want to see, if the dead…