📋 System Design Case Studies
Do each one with the System Design Case template: 45-min timed attempt → compare with references → note gaps → redo in 2 weeks.
Tier 1: classics (W10–W12)
- URL shortener (IDs, redirects, caching, analytics)
- Rate limiter (distributed, algorithms)
- Key-value store / distributed cache
- Notification system (multi-channel, retries, preferences)
- News feed / timeline (fan-out on write vs read, celebrities)
- Web crawler
Tier 2: product systems (W12–W14)
- Chat system (WhatsApp/Slack): presence, delivery receipts, ordering
- Ticket booking (BookMyShow/Ticketmaster): seat contention, flash sales, virtual waiting room
- Ride sharing (Uber): geo-indexing, matching, location updates
- Food delivery (Swiggy/Zomato): dispatch, ETAs, order state machine
- E-commerce checkout + inventory (Flipkart/Amazon): reservations, sale spikes
- Payment system: idempotency, ledger (double-entry), reconciliation
- Video streaming (YouTube/Netflix): upload pipeline, transcoding, CDN, adaptive bitrate
Tier 3: advanced (W14+, company-specific)
- Google Docs (OT/CRDT collaborative editing)
- Distributed job scheduler (cron at scale)
- Search autocomplete / typeahead
- Top-K / trending (streaming, count-min sketch)
- Ad click aggregation (stream processing, exactly-once)
- Metrics/monitoring system (time series)
- Distributed message queue (design Kafka)
- Dropbox/Google Drive (chunking, dedupe, sync)
- Proximity service / Yelp (geohash, quadtree)
- LLM-powered systems: ChatGPT-like chat service, enterprise RAG search, AI agent platform, LLM gateway
🧪 Labs (🟢 warm-up → 🟡 core → 🔴 hard → ⚫ boss)
- 🟡 1 case per week, timed at 45 min, using the System Design Case template
- 🔴 Redo each case after 2 weeks without notes; compare versions
- ⚫ Record a mock and grade yourself on structure, trade-offs, depth, and communication
🧠 Cognitive tasks
- Constraint flip on every case: 100× scale, strong consistency, multi-region
- Reverse engineering: read the real company’s engineering blog after your attempt; list 3 gaps
🛰️ Orbit integration
- Your capstone is a case study: “Design an AI workflow platform”, “Design an LLM gateway”, “Design a durable workflow engine (Temporal)”, “Design a RAG platform with ACLs”
Go deeper