Guts. Time to talk about guts. Electronics guts of course…
Which microcontroller should we use for this project? The first requirement is it hast to have WiFi, since it will be the way its way of sending notifications to my phone. About number of general purpose input/outputs (GPIO), two would be enough (one for detecting the door lock state and another one for actuating the cycle start button remotely). I could use a classic Arduino UNO, with a WiFi shield:
This one is known by most makers out there. It supports thousands of libraries, which you can make tons of things with, but… It has like 20 pins between digital and analog, and even though the WiFi shield uses some of them, I still think it’s overkill for my project. Two pins would be enough.