93040a0684
Three related UX fixes on the client. 1. Participants count on profile DMs always have exactly two participants (you and the contact) so a "Участников: 1" row was confusing — either it's obviously the other person or it's wrong depending on how you count. Removed for direct conversations; the row still appears for group chats (and shows an em-dash until v2.1.0 gives groups a real member list). 2. Dev feed seed now activates on network / 404 errors The seed was only surfaced when the real API returned an EMPTY array. If the node was down (Network request failed) or the endpoint replied 404, the catch block quietly set posts to [] and the list stayed blank — defeating the point of the seed. Now both the empty- response path AND the network-error path fall back to getDevSeedFeed(), so scrolling / like-toggling works even without a running node. Also made the __DEV__ lookup more defensive: use `globalThis.__DEV__` at runtime instead of the typed global. Some bundler configurations have the TS type but not the runtime binding, or vice-versa — the runtime lookup always agrees with Metro. 3. Back from profile → previous screen instead of tab root Root cause: AnimatedSlot rendered <Slot>, which is stack-less. When /chats/xyz pushed /profile/abc (cross-group), the chats group unmounted. Hitting Back then re-entered chats at its root (/chats list) rather than /chats/xyz. Replaced <Slot> with <Stack> in AnimatedSlot. Tab switching still stays flat because NavBar uses router.replace (which maps to navigation.replace on the Stack — no history accumulation). Cross-group pushes (post author tap from feed, avatar tap from chat header, compose modal) now live in the outer Stack's history, so Back pops correctly to the caller. The nested Stacks (chats/_layout.tsx, feed/_layout.tsx, profile/_layout.tsx) still handle intra-group navigation as before. The PanResponder-based swipe-right-to-back was removed since the native Stack now provides iOS edge-swipe natively; Android uses the system back button. animation: 'none' keeps the visual swap instant — matches the prior Slot look so nothing flashes slide-animations that weren't there before. Sub-group layouts can opt into slide_from_right themselves (profile/_layout.tsx and feed/_layout.tsx already do). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
DChain Messenger — React Native Client
E2E-encrypted mobile/desktop messenger built on the DChain blockchain stack.
Stack: React Native · Expo · NativeWind (Tailwind) · TweetNaCl · Zustand
Quick Start
cd client-app
npm install
npx expo start # opens Expo Dev Tools
# Press 'i' for iOS simulator, 'a' for Android, 'w' for web
Requirements
- Node.js 18+
- Expo Go on your phone (for Expo tunnel), or iOS/Android emulator
- A running DChain node (see root README for
docker compose up --build -d)
Project Structure
client-app/
├── app/
│ ├── _layout.tsx # Root layout — loads keys, sets up nav
│ ├── index.tsx # Welcome / onboarding
│ ├── (auth)/
│ │ ├── create.tsx # Generate new Ed25519 + X25519 keys
│ │ ├── created.tsx # Key created — export reminder
│ │ └── import.tsx # Import existing key.json
│ └── (app)/
│ ├── _layout.tsx # Tab bar — Chats · Wallet · Settings
│ ├── chats/
│ │ ├── index.tsx # Chat list with contacts
│ │ └── [id].tsx # Individual chat with E2E encryption
│ ├── requests.tsx # Incoming contact requests
│ ├── new-contact.tsx # Add contact by @username or address
│ ├── wallet.tsx # Balance + TX history + send
│ └── settings.tsx # Node URL, key export, profile
├── components/ui/ # shadcn-style components (Button, Card, Input…)
├── hooks/
│ ├── useMessages.ts # Poll relay inbox, decrypt messages
│ ├── useBalance.ts # Poll token balance
│ └── useContacts.ts # Load contacts + poll contact requests
└── lib/
├── api.ts # REST client for all DChain endpoints
├── crypto.ts # NaCl box encrypt/decrypt, Ed25519 sign
├── storage.ts # SecureStore (keys) + AsyncStorage (data)
├── store.ts # Zustand global state
├── types.ts # TypeScript interfaces
└── utils.ts # cn(), formatAmount(), relativeTime()
Cryptography
| Operation | Algorithm | Library |
|---|---|---|
| Transaction signing | Ed25519 | TweetNaCl sign |
| Key exchange | X25519 (Curve25519) | TweetNaCl box |
| Message encryption | NaCl box (XSalsa20-Poly1305) | TweetNaCl box |
| Key storage | Device secure enclave | expo-secure-store |
Messages are encrypted as:
Envelope {
sender_pub: <X25519 hex> // sender's public key
recipient_pub: <X25519 hex> // recipient's public key
nonce: <24-byte hex> // random per message
ciphertext: <hex> // NaCl box(plaintext, nonce, sender_priv, recipient_pub)
}
Connect to your node
- Start the DChain node:
docker compose up --build -d - Open the app → Settings → Node URL →
http://YOUR_IP:8081 - If using Expo Go on physical device: your PC and phone must be on the same network, or use
npx expo start --tunnel
Key File Format
The key.json exported/imported by the app:
{
"pub_key": "26018d40...", // Ed25519 public key (64 hex chars)
"priv_key": "...", // Ed25519 private key (128 hex chars)
"x25519_pub": "...", // X25519 public key (64 hex chars)
"x25519_priv": "..." // X25519 private key (64 hex chars)
}
This is the same format as the Go node's --key flag.