How to design a news feed system

· Category: System Design

Short answer

Combine push and pull fan-out strategies, cache feed fragments, and rank content by relevance or recency. Use a message queue for asynchronous fan-out. For caching strategies, see how caching improves system performance. For infrastructure, see how to choose a cloud provider.

Steps

  1. Store posts and follow relationships in a scalable database
  2. Fan out posts to followers via a message queue
  3. Precompute and cache feeds for active users
  4. Rank posts by time, relevance, or engagement
  5. Handle celebrity users with pull-based or hybrid fan-out

Tips

  • Cache the top N items of each user's feed aggressively
  • Use pagination and cursor-based fetching for infinite scroll
  • For global delivery, see how cdns speed up content delivery