A proof-of-concept ESP32 Cashu wallet that broadcasts ecash tokens over Apple's Find My network. Built on Nucula, with a Python receiver to reconstruct tokens.

Supports the Heltec WiFi LoRa 32 V3 (ESP32-S3) and the original 1.14-inch LILYGO/TTGO T-Display (ESP32).

Broadcast tokens are public bearer ecash: anyone who recovers one can spend it. Use only giveaway amounts. Delivery is slow, unofficial, and not guaranteed.

Install ESP-IDF 5.5.1; set IDF_PATH if it is outside ~/Developer/esp/esp-idf.

git submodule update --init --recursive
cp main/wifi_config.example.h main/wifi_config.h
# Edit main/wifi_config.h with your Wi-Fi credentials (ignored by Git).
./scripts/heltec.sh build
./scripts/heltec.sh flash
./scripts/heltec.sh console

In the device console:

mint add https://your-mint.example
invoice 5
# Pay the invoice, then use its quote ID:
claim <quote_id> d=1x5
findmy resume

One proof moves into a durable outbox and repeats until findmy pause. On Heltec, holding PRG for one second and releasing also starts/pauses sending. Every boot starts with transmission off. Never erase flash on a funded device.

• Heltec setup, controls, and flashing
• Receiver setup and usage — requires an Apple Account and 2FA.
• Transport protocol
• Third-party notices and license boundaries