Frontend performance means nothing if API takes 3 seconds to respond. backend optimization is frontend optimization. API performance strategies: 1. Implement efficient data fetching: // Bad: Sequential fetches (slow) async function loadDashboard () { const user = await fetchUser (); const posts = await fetchPosts ( user . id ); const comments = await fetchComments ( posts . map ( p => p . id )); return { user , posts , comments }; } // Total time: ~600ms // Good: Parallel fetches (fast) async function loadDashboard () { const [ user , posts , comments ] = await Promise . all ([ fetchUser (), fetchPosts (), fetchComments () ]); return { user , posts , comments }; } // Total time: ~200ms (fastest query wins) Enter fullscreen mode Exit fullscreen mode 2. Use GraphQL for precise data fetching: Instead of multiple REST endpoints returning excess data, GraphQL lets you request exactly what you need in one query. This reduces payload size (30-60% smaller) and eliminates multiple round trips. 3.…