System design
6 system design prompts sourced from real Walmart loops. Each one ships with scale targets, evaluation rubrics, and a reference architecture diagram.
Design a service that takes a long URL and returns a short alias. Must support billions of redirects per day with low latency, predictable IDs, and analytics on click-through.
Scale targets
Key areas
Design the system that powers a personalized timeline. Each user follows others; the home feed must be fresh, ranked, and personalized within hundreds of milliseconds.
Scale targets
Key areas
Design a 1:1 and group chat service with delivery receipts, presence, and offline message delivery. Messages must arrive in-order and survive disconnects.
Scale targets
Key areas
Design a Netflix/YouTube-style streaming platform that supports upload, transcoding, adaptive playback, and personalization. Optimize for global low-latency playback and storage cost.
Scale targets
Key areas
Design a rate limiter that protects internal services from abusive traffic. Must work across regions, share state between gateway instances, and degrade gracefully if the central store is down.
Scale targets
Key areas
Design the typeahead suggestion service for a large product search. Each keystroke must return ranked completions in well under 100ms, with personalization and trending awareness.
Scale targets
Key areas