BLE-provisioned Wi-Fi on an ESP32

The first microcontroller project, and the device side of a problem the sensor app solved another way.

A temperature and humidity sensor on an ESP32 that takes Wi-Fi credentials over Bluetooth LE, stores them in flash and posts readings to a cloud function. One commit, one weekend.

It was the first firmware in the history and the first time I wrote the provisioning dance from the device side. The same year the sensor app onboarded its devices the other way, over the device's own access point. Two answers to one problem: BLE needs no network switch on the phone, the access point needs no Bluetooth on the device.