[ubergesundheit]

I've done a similar thing with a "dumb" washing machine using a Arduino with an attached LDR (light-dependent resistor) taped to the "door open" LED.

The Arduino sends the value of the LDR over serial port to a laptop which sends changes to the "door open" over Signal to my phone

[aabdelhafez]

Side question: you can use Signal programmatically?

[ubergesundheit]

I’m using https://github.com/bbernhard/signal-cli-rest-api which exposes a REST Api