Social & Feed
Design Reddit / HackerNews (Upvoting, ranking algorithms, and tree-based comments)
A community discussion platform combining a time-decayed ranking algorithm for posts with a scalable tree-structured comment system.
Open and Simulate this Architecture in InfraDraftCore Architectural Components
Post/Submission Store
System of record for every submitted link or text post.
Vote Aggregation Service
High-throughput upvote/downvote counters decoupled from the post record.
Ranking Algorithm Engine
Time-decayed hot/best scoring that balances recency against vote count.
Tree-Structured Comment Store
Efficiently stores and retrieves arbitrarily nested comment replies.
Comment Sort/Pagination Service
Serves large comment trees incrementally without loading everything at once.
Subreddit/Community Membership Store
Community boundaries that scope posts, moderation, and feeds.
Karma & Reputation Service
Aggregates a user's vote history into a reputation signal.
Spam/Vote-Manipulation Detector
Flags brigading and bot voting patterns.