Open‑source, “zero‑power” PCB hackathon badges built with an RP2040 and e‑ink

What was built

A contributor named Kai Pereira released an open‑source design for Overglade hackathon badges that combine an RP2040 SoC, passive NFC and an onboard e‑ink driver. It has been reported that the badges' core features — the e‑ink display and NFC tap — work without a battery, which is the headline grabber here. Think low‑maintenance swag that still does tricks: passive and active NFC, 20 GPIOs exposed for tinkerers, 4 MB flash, and a PCB sporting exposed copper art. Nice to look at. Nice to hack on.

How it works and how to program it

The board is a straightforward two‑layer PCB with ground pours and CAD‑designed art for symmetry. Programming is simple: plug in over USB‑C, drop in the Pi Pico MicroPython bootloader and use Thonny to flash firmware. Users can edit a config.json and swap bitmap images (the author recommends ImageMagick for conversions). Short setup, big payoff — perfect for a hackathon quickstart.

Manufacturing, cost and community

It has been reported that the boards can be manufactured cheaply — roughly under $5 per board plus about $5 for the e‑ink in bulk — though minimum‑order PCBA runs push the upfront cost higher (the author cites about $100 for five boards with PCBA, and warns that some part orientations in the JLC assembly files may need correcting). The repo is public on GitHub (https://github.com/KaiPereira/Overglade-Badges), and the project credits the Overglade team and several contributors for firmware and art. It’s a tidy example of community hardware: playful, practical, and built for high‑school hackers. Who doesn’t love an e‑ink badge that runs on vibes and clever design?

Sources: github.com/kaipereira, Hacker News