Struggling to stay focused while preparing for software engineering interviews? PrepCommons is an experiment to address this problem using AI.https://prepcommons.com/https://prepcommons.com/blog/design-twitter/01-clarify-requirements/https://prepcommons.com/blog/design-twitter/01-clarify-requirements/Scope down "design Twitter" into something you can actually build in 45 minutes.Thu, 30 Apr 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/02-capacity-estimation/https://prepcommons.com/blog/design-twitter/02-capacity-estimation/Back-of-envelope numbers for QPS, storage, and bandwidth — and why they matter.Fri, 01 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/03-api-design/https://prepcommons.com/blog/design-twitter/03-api-design/A minimal REST surface for Twitter, with the design choices that matter.Sat, 02 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/04-data-model/https://prepcommons.com/blog/design-twitter/04-data-model/Tables, IDs, and the social graph — what to store and where.Sun, 03 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/05-high-level-architecture/https://prepcommons.com/blog/design-twitter/05-high-level-architecture/The components, the request paths, and what each one is responsible for.Mon, 04 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/06-timeline-fanout/https://prepcommons.com/blog/design-twitter/06-timeline-fanout/The single most important design decision in Twitter system design.Tue, 05 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/07-storage-and-media/https://prepcommons.com/blog/design-twitter/07-storage-and-media/Where tweets live, how media is uploaded, and why your DB never touches a JPEG.Wed, 06 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/08-caching/https://prepcommons.com/blog/design-twitter/08-caching/What to cache, how to lay it out in Redis, and how to handle cold caches.Thu, 07 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/09-search/https://prepcommons.com/blog/design-twitter/09-search/Inverted indexes, real-time indexing, and why search is its own service.Fri, 08 May 2026 23:00:00 GMThttps://prepcommons.com/blog/design-twitter/10-trending-and-bottlenecks/https://prepcommons.com/blog/design-twitter/10-trending-and-bottlenecks/Heavy-hitter algorithms, the celebrity problem revisited, and what to bring up before time runs out.Sat, 09 May 2026 23:00:00 GMT