Question 1

What rendering strategies does Next.js support?

Accepted Answer

Static, server-rendered, incremental revalidation, and client rendering — often combined per route. App Router blurs classic SSR/SSG lines via caching and dynamic APIs. A route can statically shell while streaming dynamic parts. Choose based on freshness, personalization, and TTFB needs.

Question 2

What makes a route static vs dynamic in the App Router?

Accepted Answer

Using dynamic functions/APIs (cookies, headers, uncached fetches, searchParams in certain ways) opts into dynamic rendering. Static routes can be prerendered and cached at the edge/CDN. Dynamic routes render per request. Explicit route segment config (dynamic, revalidate) documents intent. Misunderstanding this causes surprise cold TTFB.

Question 3

Explain streaming and Suspense in Next.js rendering.

Accepted Answer

HTML streams as Server Components resolve; Suspense boundaries show fallbacks for slower parts. Users see shell sooner. Place Suspense around slow data fetches. Avoid blocking the entire page on one query. Works with loading.tsx as a boundary.

Question 4

What is Partial Prerendering (PPR) conceptually?

Accepted Answer

Serve a static shell instantly while streaming dynamic holes. Combines static performance with dynamic personalization. Requires clear static/dynamic boundaries. Interviewers expect awareness of the static shell + dynamic slots mental model.

Question 5

How do searchParams affect rendering?

Accepted Answer

Reading searchParams can force dynamic rendering for that page. Design list pages carefully — caching strategies may differ for filter UIs. Consider client-side filtering for pure UX filters vs server for SEO/shareable filtered URLs.

Question 6

Lead: how do you choose rendering strategy for a product catalog?

Accepted Answer

Static/ISR for product pages, dynamic for cart/account, stream recommendations; measure cache hit rates and freshness SLAs. Define business rules for price freshness. Use on-demand revalidation for publishes. Keep personalized modules in Suspense holes so the catalog shell stays fast.

Rendering Next.js Interview Questions

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