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Voice-first Lightning wallet

BitVoice Pay

A Bitcoin Lightning wallet you operate entirely through a phone call.

MIT Bitcoin Hackathon
2nd place
2026
01020304
Signal path · 4 stages

The problem

Lightning wallets assume a smartphone, an app store, and a data plan. That excludes people who own only a basic phone.

What made it hard

The entire interface is voice and keypad over a call. No screen, no app, no device-side key storage.

Architecture

  1. 01Inbound call over Twilio Voice; PIN authenticates the caller
  2. 02Speech-to-text, then an LLM extracts intent (balance, send, receive, history)
  3. 03LNbits executes the transfer against a real Lightning wallet
  4. 04WhatsApp delivers the invoice or receipt

Outcomes

  • 2nd place at the MIT Bitcoin Hackathon 2026 (Arc VII)
  • Internal transfers on the same LNbits node settle with zero routing fees
  • Every user is issued a real Lightning wallet, not a simulation
  • Live dial-in: +1 (888) 805-6555
  • Walkthrough video: https://www.youtube.com/watch?v=a041bOCJK4k