How to redirect in route handlers?

0-2 years experience

1. 1You need to redirect a user from /old-page to /new-page after they submit a form. How would you implement the redirect inside a Next.js API route handler?
2. 2If you call res.redirect('/login') inside getServerSideProps, what will happen and why?

2-5 years experience

1. 1Your team added a feature that conditionally redirects unauthenticated users to /login from a protected page using getServerSideProps. It sometimes results in a blank page. Walk me through how you'd debug this.
2. 2Explain the trade‑offs between using next/router's push on the client versus returning a redirect object from getServerSideProps for an SEO‑critical page.

5-8 years experience

1. 1We have a high‑traffic Next.js app that needs to enforce locale‑based redirects at the edge. How would you design the redirect logic to minimize latency and avoid duplicate redirects?
2. 2During a rollout, a mis‑configured redirect caused a redirect loop for certain URLs. Describe how you would detect, isolate, and fix the loop in a production Next.js deployment.

8+ years experience

1. 1Our organization is migrating a legacy site with thousands of static URLs to a Next.js monorepo. How would you architect a maintainable redirect system that supports versioned redirects, A/B testing, and can be managed by non‑engineers?
2. 2Discuss the implications of using Next.js middleware for redirects on caching layers (CDN, Vercel Edge) and how you would ensure consistency across multiple deployment regions.