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System Design Interview

Non-Functional Requirements Network Communication Data Modeling API Design Consistent Hashing Numbers to Know

Database Blob Store Load Balancer Content Delivery Network Distributed Cache Distributed Message Queue Pub/Sub Rate Limiter

Design a URL Shortener Design a Distributed KV Store Design WhatsApp Design Twitter Design YouTube Design a Payment System Design Yelp Design Uber Design a Webhook System Design ChatGPT Design Google Docs Design Google Calendar Design an AI Rate Limiter Design a News Aggregator Design an Ad Event Aggregator Design a Hotel Booking System Design an Ads Frequency Cap

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Design WhatsApp

WhatsApp is a real-time messaging application that connects billions of users worldwide, handling 100+ billion messages daily. This question tests your understanding of WebSocket connections, message delivery guarantees, and scaling real-time systems.

This walkthrough follows the Interview Framework and focuses on what you'd actually present in a 45-60 minute interview.

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Design a Distributed KV Store

Design Twitter

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