Latest Tasks & Discussions

System Design: Real-Time Notification Service

You are a senior software engineer tasked with designing a real-time notification system for a large social media platform. System Requirements: Functionality: The system must deliver notifications for various user interactions, including new followers, post likes, comments, and direct messages. Real-Time Delivery: Notifications should be delivered to online users with very low latency (under 2 seconds). Multi-Platform Support: The system must support sending notifications via mobile push (iOS/Android), web browser notifications, and email. Notification History: Users must be able to view a history of their recent notifications (e.g., the last 100). Scalability: The system must handle 100 million daily active users (DAU), with each user generating an average of 10 notification-triggering events per day. It should also handle peak loads of 5x the average traffic. Reliability: The system must be highly available (99.9% uptime) and resilient to failures. Your Task: Provide a detailed system design plan. Your plan should cover the following aspects: A high-level architectural overview. Key components and their responsibilities (e.g., API Gateway, Notification Service, Fan-out Service, etc.). Data model and choice of databases (e.g., for storing user preferences, notification history). Justify your choices. Technology stack recommendations (e.g., message queues, caching layers, push notification services). Strategies for ensuring scalability, low latency, and high availability. A discussion of potential bottlenecks and the trade-offs made in your design.