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Social Feeds & Content Platforms

Design the systems that power billions of daily interactions — from personalized feeds to viral content delivery

Fan-out strategies Content ranking algorithms Real-time updates at scale Celebrity/hot-user handling

Twitter

Hard

Design a microblogging platform handling 500M users, 500M tweets/day with real-time fan-out, trending topics, and celebrity user optimization. Covers push vs pull feed generation.

⏱ ~3.5h
Twitter/X Meta Google

Instagram

Hard

Design a photo/video sharing platform with stories, reels, explore feed, and ML-powered content recommendations. Covers media processing pipelines and CDN strategies.

⏱ ~3.5h
Meta Google Snap

Facebook Newsfeed

Hard

Design a personalized feed for 2B+ users using ML ranking, multi-source aggregation (friends, pages, groups), and EdgeRank-style algorithms.

⏱ ~3.5h
Meta Google LinkedIn

Reddit Platform

Medium

Design a community-driven platform with subreddits, threaded comments, voting systems, and Hot/Best/New ranking algorithms.

⏱ ~3h
Reddit Meta

YouTube / Netflix

Hard

Design a video streaming platform with adaptive bitrate, transcoding pipelines, recommendation engine, and global CDN delivery.

⏱ ~3.5h
Google Netflix Amazon