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System Design at Reddit
System Design at Reddit
Reddit runs one of the largest forum-style social platforms on the internet, with a deeply nested comment model, vote-weighted ranking, and a mobile app that has to feel snappy through long browsing sessions. Interviews emphasise feed pagination, vote state management, optimistic UI, nested comments, and offline-first mobile architecture for content-heavy social products.
1 guide available•Interview focus: Feed pagination, vote state and ranking, nested comments, and offline-first social mobile apps.
Reddit System Design Interview Guides
Dec 18, 2025•20 min•
hard
Android System Design: Design Reddit
A complete Android system design guide for designing Reddit — focused on what real interviews actually ask. Covers architecture, infinite feed with Paging 3 and...
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