I’ve built an earthquake detector using the Raspberry Shake and Homebridge. You can checkout the build here - https://github.com/minkebox/homebridge_raspberryshake
I bought a Raspberry Shake back in April after stumbling across an article on these devices. I’ve always been a little obsessed with instrumenting my environment - my house is littered with temperature, humidity and air quality sensors - and being able to monitor earthquakes was a wonderful addition (and I live in the Bay Area, so I get to monitor quite a few). One thing I wanted to add to the sensor was the ability to trigger some home automations in the event of an earthquake, such as turning on lights and disabling the furnace. I already do this in case of fire, and making this earthquake enabled seems like a good safety feature.
This week I finally had time to get back to building the HomeKit piece, using the marvelous Homebridge software and the Raspberry Shake Rsudp application. The result (see the link above) uses the Rsudp application to run a tiny piece of custom Python code, which in turn prods a software sensor running in Homebridge. To simplify the whole process, I’ve wrapped it all up in a Docker image for people to play with. Please check it out.