Bolt is a high-performance, minimalist style, full-stack mobile messaging application built to deliver a "zero-latency" user experience. By combining Socket.io for persistent connections and TanStack Query for intelligent state management, Bolt ensures reliable instantaneous communication.
- Instantaneous Messaging: Bi-directional communication using WebSockets for sub-100ms message delivery.
- Modern Authentication: Secure, sign-in and sign-up flows powered by Clerk.
- Optimistic UI Updates: Messages appear in the UI immediately upon sending, with background reconciliation and syncing handled by TanStack Query levying caches.
- Persistent Sessions: Robust session management that keeps users logged in across app restarts.
- Clean & Crisp UI: A minimalist, premium design focused on readability and smooth user experience.
- React Native (Expo): Cross-platform mobile development.
- TanStack Query (v5): Handles server-state, caching, and optimistic updates.
- Clerk: Identity management and JWT-based authentication.
- Bun.js: Used as the fast JavaScript runtime to minimize startup time and overhead.
- Express & Socket.io: Powering the REST API and the WebSocket layer.
- Node.js: Core environment for scalable backend logic.
| Onboarding Flow | Chats Page | Chat Interface | User Settings |
|---|---|---|---|
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One of the main challenges was syncing Clerk’s user registration with the custom backend database. I implemented a robust onboarding flow that resolves potential race conditions, ensuring that the Socket.io connection only initializes once the user identity is fully verified and synced. The app initiates a backend sync upon returning to the foreground, keeping the displayed data up to date.
Instead of traditional Redux, I utilized TanStack Query. This allowed for:
- Automatic Refetching: Syncing message history when the app regains focus.
- Message Deduplication: Preventing the "double-message" glitch often seen in basic Socket.io implementations.
cd backend
bun install
# Add your environment variables to a .env file
# PORT, CLERK_API_KEY
bun run devcd mobile
bun install
bun run start -c