Build Uber's Surge Pricing Engine Free
Design a dynamic pricing system that detects supply-demand imbalance in each geographic zone, computes surge multipliers in under a second, and communicates price changes to riders and drivers without race conditions.
Build TinyURL - A URL Shortener at Scale Premium
Design a URL shortening service that generates collision-free short codes, handles 100,000 redirects per second with sub-10ms latency, and tracks click analytics without slowing down redirects.
Build a Video Transcoding Pipeline Free
Design a pipeline that accepts a raw 4K upload, splits it into parallel encoding jobs, produces multiple bitrate renditions, and delivers the fully processed video to the CDN in under 5 minutes.
Build a Wallet Ledger System at Scale Premium
Design a digital wallet system that records every credit and debit as an immutable ledger entry, enforces double-entry bookkeeping, and provides accurate balance reads under thousands of concurrent transactions per second.
Build Amazon's Warehouse Picking Route Optimizer Premium
Design a route optimization system for warehouse pickers that batches orders efficiently, calculates the shortest walking path through a 1M sq ft facility, and adapts routes in real-time as new orders arrive.
Build YouTube's View Count System Premium
Design a view counting system that accurately tracks billions of views per day, shows counts that update in near real-time on video pages, and resists inflation from bots and refreshes without blocking the video serve path.