index.md

System Cards (v10)

GitHub-friendly view of v10 cards. Use the links below — GitHub renders Markdown natively. For search, tabs, and interview mode, open the interactive HTML.

Easy (2)

• Scale From Zero to Millions
• URL Shortener (TinyURL)

Medium (12)

• Rate Limiter
• Consistent Hashing
• Unique ID Generator
• Web Crawler
• Notification System
• Search Autocomplete (Google Suggest)
• Google Drive / File Storage
• Proximity Service (Yelp)
• Hotel Reservation System
• Nearby Friends
• Email Service
• Real-time Gaming Leaderboard

Hard (12)

• Distributed Key-Value Store
• News Feed (Facebook/Twitter)
• Chat System (WhatsApp/Slack)
• YouTube / Video Platform
• Distributed Message Queue (Kafka)
• Payment System
• Google Maps
• Metrics Monitoring & Alerting
• Ad Click Aggregation
• Stock Exchange
• S3-like Object Storage
• Digital Wallet