LinkedIn system design interview questions
3 questions on this site are reported in LinkedIn software engineer interviews. Each is a guided run through requirements, back-of-envelope numbers, an interactive design, user flows and deep dives with interviewer follow-ups. Patterns covered: fan-out, ranking, caching, social, multi-channel, idempotency, rate-limiting, priority-queues, algorithms, counters, redis, edge.
Attribution comes from public interview guides and candidate reports, not from LinkedIn. It indicates where a question has been asked, nothing more.
Design a News Feed
The home timeline of Twitter, Instagram or Facebook: posts from people you follow, ranked, fresh, and fast for hundreds of millions of users.
Design a Notification System
Deliver push, email, SMS and in-app notifications to hundreds of millions of users: the right channel, once, on time, and never at 3 a.m.
How to prepare for a LinkedIn system design interview
Large-company loops run 45 to 60 minutes, expect numbers, and spend most of the time on deep dives. Work each question above in practice mode until you can produce the requirements, the estimates and the flows without looking, then read the interview framework guide for how to structure the hour. The other questions on the site teach patterns that show up in LinkedIn interviews under different names.
- Design a URL Shortenerkey-generation · caching · cdn
- Design Slackreal-time · websockets · fan-out
- Design a Payment Systemconsistency · idempotency · ledger
- Design YouTubetranscoding · cdn · adaptive-bitrate
- Design Google Mapsgeospatial · routing · graphs
- Design a Matchmaking Systemqueues · scheduling · latency
- Design Ubergeospatial · matching · streaming
- Design a Web Crawlerfrontier · politeness · dedupe