For weeks, I kept trying to optimize my Angular frontend endlessly. I added: Lazy loading OnPush trackBy Memoization Bundle optimizations And yet… the dashboard still felt slow. Not completely broken. Just… heavy. At first, I blamed Angular. Then I blamed rendering. Then I blamed the browser. But eventually I realized something important: Sometimes the frontend is not the bottleneck. The API architecture is. And no amount of frontend optimization can fully fix bad data flow. The Problem Nobody Talks About One dashboard page in my application required data from multiple endpoints: GET /profile GET /notifications GET /analytics GET /tasks GET /activity GET /reports At first, this looked harmless. Each component simply fetched its own data. Clean separation, right? Wrong. Because over time, the page turned into: API waterfalls loading spinners everywhere race conditions inconsistent states duplicated requests unpredictable rendering The frontend itself was optimized. But the experience still felt slow.…