// the find
sqfmi/Watchy
Watchy - An Open Source E-Ink Smartwatch
Watchy is an ESP32-based open-source smartwatch with an e-ink display that you can actually buy as hardware. It exposes the full firmware as an Arduino library, so you write custom watch faces the same way you'd write any Arduino sketch — subclass Watchy, override drawWatchFace(), flash it over USB or OTA.
The hardware/software split is clean: you buy the PCB, own the schematic, and the firmware is just an Arduino library with no vendor lock-in. The example watch faces cover enough ground (BLE sync, accelerometer step counting, weather icons, OTA updates) that you can ship something real without reading the source. E-ink means battery life measured in days, not hours, which is the one thing consumer smartwatches consistently fail at. CI workflows for three board variants (dev, main, v3) suggest the hardware has iterated and the build pipeline kept up.
The README is essentially a link farm — getting started means leaving GitHub entirely; there's almost no inline documentation for the library API, so new contributors have to read the source. The BMA423 driver is vendored C files dropped directly into src/ with no wrapper or abstraction, meaning any upstream fix requires a manual copy-paste. Watch face examples ship precompiled .bin files alongside the .ino source, which is a red flag for reproducibility and suggests the build isn't fully automated for contributors. Community support lives on Discord, which means answers rot and aren't searchable — a real cost for a hardware project where people hit the same setup issues repeatedly.