BitBoy

A stateless, QR-airgapped hobbyist hardware wallet

Workflow:

• Enter BIP39 seed on QWERTY keyboard
• (Optional) Export XPUB to desktop wallet with QR on device display
• Import unsigned PSBT with QR scanner
• After confirming outputs & fees, BitBoy will sign it
• Export signed PSBT with QR on device display

Shopping List

BitBoy

QR code airgap, keyboard. $110.

• M5stack "faces" kit ($70)
• Waveshare industrial QR scanner ($40)

BitBoy "lite"

MicroSD airgap. $42.

• M5Stack ($37)
• MicroSD card ($5)

How it works:

• Base MicroPython firmware
  • Bitcoin primitives
  • Drivers for display, buttons, keyboard
• bitboy.py in this repo contains the hardware wallet logic itself. It's a modern asyncio event loop!
• wallet.py is a primitive watch-only wallet leveraging Bitcoin Core
• ui.py is a shitty UI connecting BitBoy and wallet.py / Bitcoin Core
• Eventually I want this all to work in Junction

Status

This is alpha software, testnet-only for now.

If you'd like to build one, buy the items in the shopping list. Instructions will be posted in the next week. You can DM Justin with questions on Twitter.