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dfc2b8dcd1
Two problems Codex found in the first push. "SOCKS connection error" is not a circuit failure. arti-build logs that wrapper for every error out of handle_socks_connection, including local protocol faults raised before a circuit is attempted — "Invalid SOCKS handshake", "Unsupported SOCKS version", "Unsupported SOCKS command". Anything on the device that speaks SOCKS badly to the local port would have read as a dead Tor. Drop it. "Failed to connect through Tor" is logged only on client.connect() failure, and "Failed to obtain exit circuit" is arti's own detail for that error, which is what #610 shows — so the reported lines are still matched. The restart path cancels itself. restartArti stops Arti first, and stopArtiInternal cancels retryJob and inactivityJob. Both existing recovery paths call restartArti from inside one of those jobs, so the coroutine is cancelled between the stop and the start and Arti never comes back. That is already true on main for the start-failure and bootstrap-inactivity paths; routing a post-bootstrap outage into it would have turned a wrong indicator into a stopped Tor, which is worse. Run restarts from a separate restartJob that the stop path leaves alone, and cancel it explicitly when the user turns Tor off so a pending recovery cannot resurrect it.
bitchat for Android
A decentralized peer-to-peer messaging app with dual transport architecture: local Bluetooth mesh networks for offline communication and internet-based Nostr protocol for global reach. No accounts, no phone numbers, no central servers.
This is the Android implementation of bitchat, fully protocol-compatible with the iOS version for cross-platform mesh communication.
See it in action
| Offline mesh conversation | Geohash globe picker |
|---|---|
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 |
License
This project is released into the public domain. See the LICENSE file for details.
Features
- Dual Transport Architecture: Bluetooth LE mesh for offline messaging, Nostr relays for internet-based messaging
- Location-Based Channels: Geographic chat rooms using geohash coordinates over Nostr relays
- Intelligent Message Routing: Automatically chooses the best transport, with queuing and retry when a peer is unreachable
- End-to-End Encryption: Noise Protocol (XX pattern, X25519 + ChaCha20-Poly1305) for private messages over the mesh
- Decentralized Mesh Network: Automatic peer discovery and multi-hop relay over Bluetooth LE (max 7 hops)
- Wi-Fi Aware Transport: Higher-bandwidth local mesh on supported devices
- Channel Chats: Topic-based group messaging with optional password protection (Argon2id + AES-256-GCM)
- IRC-Style Commands: Familiar
/join,/msg,/whostyle interface - Tor Support: Built-in Tor (Arti) for private internet connectivity
- Emergency Wipe: Triple-tap to instantly clear all data
- Cross-Platform: Binary protocol compatible with bitchat on iOS and macOS
Technical Architecture
Bluetooth Mesh Network (Offline)
- Direct peer-to-peer within Bluetooth range, multi-hop relay through nearby devices
- Noise Protocol sessions with forward secrecy; peer identities derived from static keys
- Compact binary packet format with fragmentation, TTL routing, and deduplication
- Adaptive duty cycling and connection limits for battery efficiency
- Foreground service keeps the mesh alive within Android background execution limits
Nostr Protocol (Internet)
- Global reach via public relays, geohash-based location channels
- Private messages fall back to Nostr for mutual favorites when the mesh is unavailable
- Ephemeral keys per geohash area
Android Stack
- Kotlin, Jetpack Compose (Material 3), MVVM
- Coroutines and Flow for all networking and state
- Core components:
MeshForegroundService(persistent connectivity),BluetoothMeshService/WifiAwareMeshService(transports),UnifiedMeshService(transport selection),NoiseSessionManager(encryption sessions),MessageRouter(mesh/Nostr routing with outbox retry)
Building
Requires Android Studio and the Android SDK (API 26+).
git clone https://github.com/permissionlesstech/bitchat-android.git
cd bitchat-android
./gradlew assembleDebug
Install on a connected device:
adb install -r app/build/outputs/apk/debug/app-debug.apk
The app requests Bluetooth, location (required for BLE scanning), and notification permissions at runtime.
Release APKs and the Android App Bundle can be rebuilt byte-for-byte in the pinned Linux container. Maintainers should follow the Android release guide. See Reproducible builds for the build trust model and public GitHub/Google Play verification procedures.
Testing
# Unit tests
./gradlew test
# Lint
./gradlew lint
# Instrumented tests (requires a device or emulator)
./gradlew connectedAndroidTest
Note that BLE mesh behavior is difficult to emulate; protocol and session logic is covered by unit tests, while radio-level behavior needs real devices.