Bitchat And Chill 2025 08 14
Date: 2025-08-14
Presenter: Round Rock Bitcoiners
Outline & Notes
Bitchat and Chill: Offline Bitcoin & Mesh Networking
Source: RRBTC (Round Rock Bitcoiners #38) Date: August 14, 2025
Problem & Solution
- Problem: Bitcoin wallets require network to broadcast transactions. Black-out scenarios make P2P value transfer impossible.
- Solution: Combine offline mesh networking with privacy-preserving eCash (Cashu)
Mesh Network Comparison
| Category | Radio | Examples | Use-Case | | Wi-Fi Mesh | 2.4/5 GHz | 802.11s, Google Nest | Home/City broadband | | Bluetooth Mesh | BLE | Bitchat, Briar | Secure local chat | | LoRa Mesh | Sub-GHz | Meshtastic | Long-range (km), low-bandwidth | | Hybrid | Multiple | Briar, Yggdrasil | Disaster response |
Key Platforms
- Bitchat (Jack Dorsey): Encrypted messenger over BLE. Noise Protocol, multi-hop relays. Payload ~512B.
- Meshtastic: Open-source LoRa firmware. Range 1-5 km. Max payload ~242B.
- Briar: Decentralized Android messenger. Bramble protocol, store-and-forward. Android-only.
Cashu + eCash Workflow
- Mint: User creates token while online
- Sender: Copies token (Base64) to clipboard
- Transfer: Sends via Bitchat/Briar/Meshtastic while offline
- Receiver: Gets encrypted message via mesh hop
- Redeem: Redeems with mint once back online
Future Considerations
- Trust in mint required
- Scalability of BLE hops in crowds
- Community-run Cashu mints
- Mesh-first Bitcoin wallets
Slides in this Deck
- Deck Overview (All Slides)
- Slide 1
- Slide 2
- Slide 3
- Slide 4
- Slide 5
- Slide 6
- Slide 7
- Slide 8
- Slide 9
- Slide 10
- Slide 11
- Slide 12
- Slide 13
- Slide 14
- Slide 15














