How Reddit Builds a Different Website for Every Single User (A System Design Breakdown)

How does Reddit serve millions of completely different front pages at the exact same second? This video breaks down the real system design behind Reddit’s architecture — from personalized ranking algorithms to nested comment trees, real-time vote aggregation, decentralized moderation, and search infrastructure built to handle over a decade of posts and comments.

We cover how Reddit’s platform is really thousands of independently moderated subreddits running on one shared backend, and how the fr