3074fa0fcb
* BinaryProtocol: add optional padding control; BitchatPacket API for padded/unpadded bytes; BLEService: use unpadded encoding and remove ad-hoc unpadding on BLE writes * BLEService: balance BLE padding — pad Noise handshake/encrypted frames; leave public/announce/leave unpadded; keep fragmentation consistent with chosen padding * BLEService: replace Timer with DispatchSourceTimer on bleQueue; NostrTransport: cache placeholder NoiseEncryptionService to avoid reallocation * Unify peerID validation: InputValidator handles 16-hex, 64-hex, or alnum-/_; NoiseSecurityValidator now delegates to InputValidator * UI: use standard green for geohash toolbar badge and count (less bright in light mode) * UI: standardize geohash sheet green to app standard (dark: system green, light: darker green) for buttons and checkmark * Docs: align BinaryProtocol compression docs to zlib; Logs: reduce NostrTransport DELIVERED ack logs to debug to cut noise * Tests: add InputValidator peerID coverage and BinaryProtocol padding round-trip/length tests * Project: ensure Xcode project reflects new tests (references added) --------- Co-authored-by: jack <jackjackbits@users.noreply.github.com>
bitchat
A decentralized peer-to-peer messaging app that works over Bluetooth mesh networks. No internet required, no servers, no phone numbers. It's the side-groupchat.
Warning
Private messages have not received external security review and may contain vulnerabilities. Do not use for sensitive use cases, and do not rely on its security until it has been reviewed. Now uses the Noise Protocol for identity and encryption. Public local chat (the main feature) has no security concerns.
License
This project is released into the public domain. See the LICENSE file for details.
Features
- Decentralized Mesh Network: Automatic peer discovery and multi-hop message relay over Bluetooth LE
- Privacy First: No accounts, no phone numbers, no persistent identifiers
- Private Message End-to-End Encryption: Noise Protocol
- IRC-Style Commands: Familiar
/slap,/msg,/whostyle interface - Universal App: Native support for iOS and macOS
- Emergency Wipe: Triple-tap to instantly clear all data
- Performance Optimizations: LZ4 message compression, adaptive battery modes, and optimized networking
Technical Architecture
Binary Protocol
bitchat uses an efficient binary protocol optimized for Bluetooth LE:
- Compact packet format with 1-byte type field
- TTL-based message routing (max 7 hops)
- Automatic fragmentation for large messages
- Message deduplication via unique IDs
Mesh Networking
- Each device acts as both client and peripheral
- Automatic peer discovery and connection management
- Adaptive duty cycling for battery optimization
For detailed protocol documentation, see the Technical Whitepaper.
Setup
Option 1: Using XcodeGen (Recommended)
-
Install XcodeGen if you haven't already:
brew install xcodegen -
Generate the Xcode project:
cd bitchat xcodegen generate -
Open the generated project:
open bitchat.xcodeproj
Option 2: Using Swift Package Manager
-
Open the project in Xcode:
cd bitchat open Package.swift -
Select your target device and run
Option 3: Manual Xcode Project
- Open Xcode and create a new iOS/macOS App
- Copy all Swift files from the
bitchatdirectory into your project - Update Info.plist with Bluetooth permissions
- Set deployment target to iOS 16.0 / macOS 13.0
Option 4: just
Want to try this on macos: just run will set it up and run from source.
Run just clean afterwards to restore things to original state for mobile app building and development.