Build a scalable social graph that handles complex relationship queries (e.g., mutual friends).
Technical Implementation: Use a Self-Referential Join table in a relational database or, for better performance, a Graph Database (Neo4j). Create indexes on follower_id and following_id. Implement a Fan-out strategy for activities: when a user posts a trip, use a background worker (like BullMQ or Celery) to push that update to the feeds of all their followers.
What is Not Accepted: Counting followers using SELECT COUNT(*) on every request; you must use Counter Caching. Circular dependencies or "ghost" follows from deleted accounts. O(N) lookups for mutual connections.
Build a scalable social graph that handles complex relationship queries (e.g., mutual friends).
Technical Implementation: Use a Self-Referential Join table in a relational database or, for better performance, a Graph Database (Neo4j). Create indexes on follower_id and following_id. Implement a Fan-out strategy for activities: when a user posts a trip, use a background worker (like BullMQ or Celery) to push that update to the feeds of all their followers.
What is Not Accepted: Counting followers using SELECT COUNT(*) on every request; you must use Counter Caching. Circular dependencies or "ghost" follows from deleted accounts. O(N) lookups for mutual connections.