5 min read A news feed service delivers a ranked, personalized stream of posts to each user. The central design question is delivery […] Read article
5 min read A password manager is security-critical software. Every design decision either exposes user secrets or protects them. The central architectural constraint […] Read article
7 min read Overview A data anonymization service transforms raw datasets containing personally identifiable information (PII) into privacy-safe versions that can be used […] Read article
5 min read Problem Statement Design a peer-to-peer payment service that lets users send money to one another, link external bank accounts, and […] Read article
6 min read Problem Statement Design the order book engine for a crypto exchange: handle limit and market orders, match them using price-time […] Read article
6 min read What Is a Ride-Share Matching System? A ride-share matching system pairs riders who need a trip with nearby available drivers. […] Read article
6 min read What Is a Delivery Tracking Service? A delivery tracking service monitors the lifecycle of a shipment from pickup through final […] Read article
5 min read What Is a Gift Card Service? A gift card service handles the full lifecycle of stored-value cards: issuance, activation, balance […] Read article
6 min read What Is a Promotional Code Engine? A promotional code engine generates discount codes, enforces usage rules, validates eligibility at checkout, […] Read article
6 min read What Is a User Feedback Service? A user feedback service collects structured and free-form feedback from users across product surfaces, […] Read article