System Design Case Studies
Guided designs with trade-offs, alternatives, and best practices.
URL Shortener
High-read key-value service with redirect at scale.
Rate Limiter
Token bucket, sliding window, and distributed rate limiting.
Notification System
Push, email, and SMS delivery at millions per hour.
Chat System
Real-time messaging with WebSockets, presence, and history.
Video Streaming
Upload, transcoding pipeline, and global CDN delivery.
Social Feed
Fan-out on write vs read, ranking, and celebrity problem.
Ride Sharing
Geospatial matching, real-time location, and pricing engine.
Payment System
Idempotency, exactly-once processing, and double-spend prevention.
Distributed Cache
Consistent hashing, eviction, and cache coherence at scale.
Search Engine
Web crawling, inverted index, and ranking at internet scale.
Cloud Storage
Block storage, metadata service, and durability at exabyte scale.
Recommendation Engine
Collaborative filtering, feature stores, and real-time serving.