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Next.js Migration

Migrate your legacy React / Angular / Vue app to Next.js App Router. SSR, SSG, ISR, React Server Components—zero regression, from €2,500.

Key takeaways

Migrate your legacy React / Angular / Vue app to Next.js App Router. SSR, SSG, ISR, React Server Components—zero regression, from €2,500.

  • ›Core Web Vitals GOOD rating across all pages—clients typically see a 40–60% improvement in Largest Contentful Paint (LCP) after migration.
  • ›Full App Router adoption with React Server Components—pages that don't need interactivity become zero-JS server-rendered HTML, slashing bundle size.
  • ›Route-by-route incremental migration—no big-bang rewrite. Production traffic is unaffected throughout the entire process.

Price: from €2,500

SERVICE DETAILS

I migrate web applications of all sizes to Next.js 16+ App Router with React Server Components, delivering immediate SEO and Core Web Vitals gains. My process is regression-free: I run the legacy and Next.js builds in parallel, migrate route by route, and cut over only when every page passes automated Playwright tests. You keep your existing design; what changes is the rendering architecture and the Google ranking.

› INVESTMENT:

from €2,500
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Key Benefits

Core Web Vitals GOOD rating across all pages—clients typically see a 40–60% improvement in Largest Contentful Paint (LCP) after migration.

Full App Router adoption with React Server Components—pages that don't need interactivity become zero-JS server-rendered HTML, slashing bundle size.

Route-by-route incremental migration—no big-bang rewrite. Production traffic is unaffected throughout the entire process.

TypeScript migration included—if your codebase is plain JavaScript, I convert it to strict TypeScript in the same pass at no extra cost.

Automated Playwright regression testing suite built during migration so future releases cannot break the UI silently.

The Process

1

Audit & Migration Plan

I audit your existing routing structure, state management, API calls, and third-party integrations, then produce a route-by-route migration plan with risk assessment and estimated timeline.

2

Infrastructure Setup

I bootstrap the Next.js App Router project, configure ESLint, TypeScript, Tailwind or your existing CSS framework, and the CI/CD pipeline before migrating a single page.

3

Page-by-Page Migration

I migrate pages incrementally, starting with the highest-traffic routes. Each migrated page passes a Lighthouse audit and automated regression tests before the next one begins.

4

Cut-over & Monitoring

I point production DNS to the new Next.js deployment, monitor Core Web Vitals in real time via the CrUX API, and keep the old server live for 48 hours as an instant rollback fallback.

Frequently Asked Questions

How long does a migration take?

A 10–20 page marketing site takes 2–3 weeks. A complex SaaS product with 50+ routes takes 6–10 weeks. I provide a precise estimate after the initial codebase audit, with a fixed-price option available.

Will the migration break my existing URLs and SEO rankings?

No. I map every existing URL to its Next.js equivalent and set up 301 redirects for any that change, fully preserving your Google ranking equity and backlink profile.

My app uses Redux heavily—will that be a problem?

Redux runs on the client side and is fully compatible with Next.js. I identify which state can be moved to Server Components (reducing JS bundle) and which must stay client-side, giving you the best of both worlds.

Do you migrate to the Pages Router or App Router?

Always App Router (Next.js 13+). Pages Router is in maintenance mode. If your deadline is extremely tight, I can start with Pages Router and plan an App Router upgrade as a clearly scoped phase 2.

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BIAŁYSTOK, PL
+48 732 022 086pawel.wiszniewski95@gmail.com