Next.js bundle analyzer for targeted performance work

Performance work is hard when you’re guessing what’s in your bundle. The bundle analyzer turns it into a visual diff: you can see which dependencies are big and whether code splitting is working. I gate it behind an env var like ANALYZE=true so it’s opt-in and doesn’t slow down normal builds. The practical approach is looking for unexpected heavy deps (moment, big editor packages, charting libs), then fixing with lazy loading or smaller alternatives. It also helps catch accidental server-only modules pulled into the client bundle. With the analyzer in place, reviews become concrete: ‘this chunk grew by 200KB’ is actionable; ‘it feels slower’ isn’t.