Post by Muhammad Haseeb Akram

Ever wondered how LinkedIn generates your feed so fast? Behind the scenes, one of the concepts used at scale is "Fan-Out on Read". Imagine someone with 100K+ followers publishes a post. Does the platform instantly copy that post into 100,000 feeds? ❌ Not necessarily. With Fan-Out on Read, the system stores the content once and only generates your feed when you open the app. Simple flow: 📝 Post created 💾 Store once 📲 User opens app 🔎 Fetch followed users’ content 🧩 Build feed in real time Why companies use it: ✅ Better storage efficiency ✅ Handles massive creator scale ✅ Works well for high-content platforms Tradeoff: ⚠️ Feed generation can add read latency. System design is full of tradeoffs — and understanding them changes how you think about products #systemDesign #PM