bitchat - dstealth

A private "offline-first" chat app with built-in Post-Quantum ethereum wallet. Sign transactions and broadcast them over bluetooth mesh network to find a peer connected online to relay it to a RPC.

Videos

Tech Stack

Rust

Solidity

Swift

Helios

TOR

Dilithium

ML-DSA44

BLE mesh

Description

bitchat - dstealth

Offline-first, decentralized messaging with a post-quantum ERC-4337 smart wallet — built for iOS and macOS, live on the App Store today.

Triple Transport Architecture

BLE Mesh — Multi-hop Bluetooth relay (up to 7 hops) with Noise_XX_25519_ChaChaPoly_SHA256 encryption. Zero infrastructure. Works in disasters, protests, off-grid.

Nostr — Location-based geohash channels over 290+ global relays with NIP-17 gift-wrapped DMs and ephemeral per-channel identity.

XMTP — MLS-encrypted wallet-to-wallet group messaging with WalletSendCalls (XIP-59) for in-chat DeFi transactions and bot/agent integration.

All internet traffic is Tor-routed by default (fail-closed). No accounts, no phone numbers, no servers.

Post-Quantum Smart Wallet (Arbitrum)

Hybrid ECDSA secp256k1 + ML-DSA-44 (FIPS 204) ERC-4337 account via ZKNOX factory contracts. Both signatures required for every UserOperation — secure even if either scheme is broken.

Stealth PQ addresses (Fluidkey-style) with offline CREATE2 prediction, deploy-on-sweep, and auto-rotating ENS via Namestone (alice.pq.dstealth.eth)

Offline transaction signing relayed through BLE mesh to online peers who broadcast via Flashbots Protect

Trustless verification: a16z's Helios light client compiled to iOS via Rust FFI provides consensus-verified balance queries — no RPC trust required. 3-tier fallback: Helios → Merkle proof → raw RPC.

PQBeat — Stage 1 Wallet

github.com/ZKNoxHQ/PQbeat

bitchat is one of the first mobile wallets with production PQ smart account support:

PQBeat Criteria | bitchat

PQ Key Generation | ✅ ML-DSA-44 (SwiftDilithium, FIPS 204)

PQ Smart Account | ✅ ZKNOX mldsa_k1 factory on Arbitrum

PQ Signing | ✅ Hybrid ECDSA + ML-DSA-44 for every UserOp

Chain Stage | Stage 1 (ERC-4337 + PQ signature verification via smart contract)

Among wallets tracked by PQBeat, only ZKNOX's own reference implementation currently meets these criteria.

Walletbeat — Evaluation Pillars

github.com/walletbeat/walletbeat

bitchat targets top marks across all six walletbeat evaluation pillars:

Pillar | How bitchat delivers

🔒 Security | Hybrid PQ signatures, Noise Protocol forward secrecy, rate limiting, replay protection, PKCS#7 traffic analysis padding

😎 Privacy | Tor-by-default, ephemeral keys per geohash, stealth addresses, zero persistent identifiers, triple-tap panic wipe

🏰 Self-sovereignty | No accounts, no servers, no phone numbers, offline-capable, local-only key storage (Keychain), emergency data wipe

🕵 Transparency | Public domain license, fully open source, no telemetry

🌳 Ecosystem | ERC-4337, ERC-1271, Aave V3 DeFi integration (WIP), ENS subdomains, XMTP interop, Nostr interop

🛠️ Maintenance | Active development, live on App Store, 21+ test suites

Stack

Swift/SwiftUI · Noise Protocol · Nostr · XMTP · SwiftDilithium (ML-DSA-44) · ERC-4337 v0.7 · Helios (Rust FFI) · Tor (Arti SOCKS5) · Arbitrum

📲 App Store: https://testflight.apple.com/join/6K2GC9wN · 🔓 Public Domain · 🌐 dstealth.xyz

Progress During Hackathon

bitchat fork — Progress Summary Fork: permissionlesstech/bitchat from 21-DOT-DEV/bitchat Period: January – February 2026 Commits since fork: 41 Lines added: ~20,400 across 55 Swift files, plus docs, configs, and tests 1. MESH TRANSACTION RELAY (OFFLINE BLE TRANSACTIONS) Sign Ethereum transactions offline and broadcast them through the BLE mesh — nearby online peers relay to the network. 2. POST-QUANTUM ERC-4337 SMART ACCOUNT Hybrid ECDSA secp256k1 + ML-DSA-44 (FIPS 204) smart account via the ZKNOX factory — quantum-resistant on-chain wallet deployed on Arbitrum Sepolia. 3. STEALTH PQ ACCOUNTS (FLUIDKEY-STYLE PRIVACY) Fluidkey-inspired stealth address system — but swapping the Safe 1/1 for a ZKNOX PQ Account. Rotate a fresh counterfactual address for every payment; deploy the smart account only when sweeping funds. Status: Fully implemented on Arbitrum Sepolia. All phases complete. 4. XMTP TRANSPORT LAYER Added XMTP as a third transport alongside BLE mesh and Nostr — enabling MLS-encrypted group messaging, wallet-native identity, and an in-app CLI. 5. NAMESTONE ENS INTEGRATION Gasless ENS subdomains for every bitchat user via Namestone's offchain resolver on dstealth.eth. 6. pq.dstealth.eth ENS NAMESPACE Dedicated subdomain namespace for stealth PQ account addresses — the receiving counterpart to dstealth.eth identity names. 7. HELIOS LIGHT CLIENT (TRUSTLESS VERIFICATION) a16z's Rust Ethereum light client compiled to an iOS xcframework — turns untrusted Tor-routed RPC into consensus-verified responses. 8. ADDITIONAL CHANGES Tor (Arti SOCKS5 — Fail-Closed): All internet traffic Tor-routed by default. Replaced legacy C Tor with Rust Arti (smaller binary, better iOS lifecycle). Fail-closed: if Tor is down, network requests block rather than leak clearnet. The Tor replacement landed before the fork in PRs #957–#958, but XMTP and Helios traffic routing is new work. XMTP CLI Command Engine: CommandProcessor.swift expanded by +1,202 lines — unified slash-command engine supporting both Nostr and XMTP contexts. Commands include /dm, /group, /wallet-send, /balance, /ens, /peer-info, and more. Send Transaction View: SendTransactionView.swift (+406 lines) — supports sending from both EOA wallet and PQ smart account, gas estimation, Tor-routed broadcast, and offline mesh relay fallback. Transaction Store: TransactionStore.swift (179 lines) — local persistence for pending, relayed, and confirmed transactions. Secure Config: SecureConfig.swift (39 lines) — centralized secure configuration for API keys and RPC endpoints, loaded from Keychain. App Info and UI: AppInfoView.swift displays Helios status, PQ account status, and Tor circuit info. ContentView.swift integrates PQ wallet and Helios into the main navigation. LocationChannelsSheet.swift adds geohash channel UI improvements. MeshPeerList.swift shows mesh peer display with relay capability indicators. CommandSuggestionsView.swift updated for the expanded command set. SUMMARY Mesh Tx Relay — 3 files, ~870 lines added PQ Smart Account — 10 files, ~4,900 lines added, 21 tests Stealth PQ Accounts — 3 files, ~1,490 lines added, 21 tests XMTP Transport — 6 files, ~3,830 lines added Namestone ENS — 2 files, ~540 lines added pq.dstealth.eth — 3 files, ~1,560 lines added Helios Light Client — 6 files, ~4,030 lines added, 445 lines of tests Other (CLI, Views, etc.) — 12+ files, ~3,500 lines added Total: 55 files changed, ~20,400 lines added, 42+ tests All Ethereum operations are Tor-routed and (where Helios is running) consensus-verified. All PQ signatures use the hybrid ECDSA + ML-DSA-44 scheme — quantum-resistant today, classical-secure as fallback.

Fundraising Status

Looking for and interested in finding funding to bring this to production.

Team Leader

TTantodefi

Project Link

Sector

SocialFiDeFiInfra