Technology Stack
Modern, battle-tested technologies for reliability and performance
Frontend
React Native
Cross-platform mobile framework for iOS & Android
TypeScript
Type-safe JavaScript for robust development
Redux
State management for complex app state
React Navigation
Routing and navigation for mobile apps
Why React Native?
- • Single codebase for iOS and Android
- • Native performance and feel
- • Large community and ecosystem
- • Easy to hire experienced developers
Backend
Node.js
JavaScript runtime for server-side development
Express
Lightweight web framework for APIs
PostgreSQL
Relational database for user & group data
MongoDB
NoSQL database for scalable chat history
Redis
In-memory cache for sessions & real-time features
Database Strategy
Dual-database approach for optimal performance:
- PostgreSQL: User accounts, groups, permissions, metadata
- MongoDB: Chat history (scales horizontally), media metadata
- Redis: Session management, real-time presence, caching
Security & Encryption
libsignal-protocol
Signal Protocol implementation for E2EE
OMEMO
Group E2EE encryption standard
TLS 1.3
Secure transport layer encryption
bcrypt
Password hashing for authentication
Encryption Pipeline
Client-side: Messages encrypted before transmission using Signal Protocol
Transport: TLS 1.3 for additional transport security
Server: Messages stored encrypted. Server never has decryption keys.
Delivery: Decryption happens only on recipient device
Infrastructure & DevOps
Docker
Containerization for consistent deployments
Kubernetes
Container orchestration for scalability
GitHub Actions
CI/CD pipeline automation
Sentry
Error tracking and monitoring
Grafana
Metrics visualization and alerting
Deployment Strategy
- • Containerized services for consistency
- • Kubernetes for auto-scaling and high availability
- • Multi-region deployment for low latency
- • Automated rollbacks for failed deployments
Real-Time & Notifications
Socket.io
WebSocket library for real-time messaging
Firebase Cloud Messaging
Push notifications (FCM)
Apple Push Notification
Push notifications (APNs)
Messaging Architecture
- • WebSocket connections for instant delivery
- • Message queuing for offline users
- • Push notifications for background delivery
- • Automatic retry with exponential backoff
Performance Targets
Message Delivery
UI Response Time
Uptime SLA