Next.js in SaaS: Why App Router & Server Components Matter

I rebuilt a SaaS dashboard prototype in Next.js 14 and compared it with a previous Pages Router setup. What changed: • Server Components reduced client JS a lot (billing history table: ~90kb → ~20kb). • Route Handlers replaced my ad‑hoc API folder — fewer moving parts, easier auth layering. • Server Actions simplified form posts: no juggling mutations for simple CRUD. Best fit: multi‑tenant dashboards where performance and data flow predictability matter. Caution: highly interactive UIs still need careful hydration strategy. Net: Next.js lets SaaS teams spend more time on product logic and less on wiring.