Coffee Roaster
A complete coffee roasting system I built from scratch. The journey spans C++ firmware on an ESP32, a MicroPython rewrite with a web API, and a React Native companion app for real-time monitoring and profile management.
This project started as a way to roast my own coffee at home with precise control over the temperature curve. It evolved into a three-part system that spans the entire stack — from reading sensor data on a microcontroller to charting it in real-time on a phone.
The original firmware was written in C++ with PlatformIO, supporting OTA updates and Husarnet for remote access. I later rewrote it in MicroPython for faster iteration, adding a web API with Server-Sent Events for real-time temperature streaming.
The React Native companion app connects to the roaster over the local network, displays live temperature charts, and lets me save and load roasting profiles. The whole system works offline — no cloud dependency.