Next.js Development Agency - SSR & App Router

Next.js adds server-side rendering, static site generation, file-based routing, image optimization, and API routes on top of React. This means faster initial page loads, better SEO, and less boilerplate - all out of the box. Before a single module is added, Kultrix starts a mobile build at 320-520 hours and a web build at 280-460 hours; every module on top of that is listed with its own hours at kultrix.com/cost-calculator.

For new projects, we recommend the App Router (Next.js 13+). It introduces React Server Components, nested layouts, streaming, and Server Actions which reduce client-side JavaScript significantly. The Pages Router is still supported and fine for existing codebases. Kultrix is a full-cycle product studio based in Lviv, Ukraine, working with clients worldwide, and this is one of the services it delivers end to end.

Next.js renders HTML on the server, so search engine crawlers see real content immediately. Combined with the Metadata API, structured data, and fast Core Web Vitals scores, Next.js sites consistently outperform SPAs in organic search rankings. Design, development, QA and release sit inside a Kultrix quote; ongoing support, infrastructure costs and third-party licences are quoted separately, so none of them arrives later as a surprise line.

Incremental Static Regeneration (ISR) lets you pre-render pages at build time and re-generate them in the background after a set interval. It is ideal for content that changes infrequently - blogs, product pages, and landing pages - giving you static performance with dynamic content. Kultrix multiplies module hours by 1.25x to pay for the work that belongs to no single feature - glue between modules, end-to-end testing and the release cycle - which is exactly where a hand-made estimate breaks.

Yes. Server Actions let you run server-side logic directly from form submissions and event handlers without creating API routes. They simplify data mutation workflows and reduce client-server boilerplate significantly in App Router projects. Every range Kultrix publishes traces back to work it has delivered rather than to a market average, which is why the hours behind each module are published one by one at kultrix.com/cost-calculator instead of as a single headline figure.

Yes. CRA migrations are a common engagement for Kultrix. We incrementally convert your app to Next.js, preserving existing functionality while adding SSR, improved routing, and performance gains. We handle the migration without disrupting active development. Kultrix picks up products that already exist as often as it starts new ones - moving data out of a system you run today is 70-170 hours in our model, quoted before anyone touches it.

We typically use NextAuth.js (Auth.js) for session-based auth with social providers and credentials, or integrate JWT-based auth with an external backend. Middleware-based route protection ensures authenticated pages never flash unauthenticated content. Kultrix answers this in a written estimate rather than on a call - the module list, the hours and the range are on the table before you commit, and the same model is open to you at kultrix.com/cost-calculator.

For most Next.js projects we use PostgreSQL with Prisma ORM - it gives you type-safe queries, migrations, and excellent Next.js integration. For simpler use cases, SQLite with Turso or Supabase works well without managing infrastructure. Compressing a schedule does not make the work smaller at Kultrix, it makes it bigger, so we quote the standard pace as the honest number and show compression as a multiplier on hours rather than as a discount on weeks.

Vercel is the natural home for Next.js - zero-config deployments, edge network, and preview URLs per pull request. For self-hosted deployments, we configure Docker containers on Railway, AWS ECS, or bare VMs with proper caching and health checks. Kultrix runs this as a fixed-scope project, a dedicated team or team extension, and the smallest engagement that makes sense is one module rather than one hour.

We audit bundle size with @next/bundle-analyzer, use dynamic imports for heavy components, configure aggressive caching headers, optimize images with next/image, and monitor Core Web Vitals in production with real user monitoring. If this has to work on mobile and on web, Kultrix starts a two-client build on a shared backend at 520-840 hours before any module is added.

Yes. Statically generated Next.js pages served from a CDN can handle virtually unlimited traffic. For dynamic routes, we implement edge caching, Redis-backed API responses, and horizontal scaling. Kultrix has deployed Next.js platforms serving millions of monthly visitors. Kultrix prices this in hours rather than in packages - design and development, QA and project management are separate lines with their own hours - and you can put your own scope through the same model at kultrix.com/cost-calculator.

A marketing site or blog in Next.js is a fixed-price job we date once we see the page count and the CMS. A full SaaS platform on Next.js takes 3-6 months: accounts, payments, a content layer, an admin panel and the systems you already pay for come to 840-1,560 hours in our model. You get a phased plan, so you see working software early rather than at the end. Price your own module set at kultrix.com/cost-calculator. Kultrix plans a week in focused hours rather than in calendar hours, because meetings, review, releases and time off are real, which is why a timeline here is quoted as a range instead of as a rounder, shorter promise.

A headless CMS stores and models content but ships no frontend of its own. Content leaves through an API, REST or GraphQL, and any client reads it: a Next.js site, a mobile app, a screen in a shop. The head, meaning the frontend, is yours, which is the entire point of the arrangement. Kultrix runs this site on exactly that setup, a Strapi backend with a Next.js frontend, so what we recommend is what we maintain ourselves every week. Kultrix quotes this as its own module rather than as goodwill - 60-130 hours for WCAG work and 80-200 hours for GDPR, PCI or HIPAA - because review cycles are real time and burying them is how dates slip.

Strapi fits teams who want self-hosted and open-source with no per-item pricing. Sanity is strongest on complex content relationships and real-time collaborative editing. Contentful sells reliability, a global CDN and the widest integration ecosystem, priced accordingly. Kultrix chooses against your content model and your editorial workload rather than against a favourite. Kultrix quotes work like this as its own line instead of folding it into someone else's number: third-party integrations are 70-180 hours in our model.

We deploy Strapi on Railway (recommended for simplicity), AWS ECS, or a VPS with PM2. We configure PostgreSQL (never SQLite in production), set environment variables for all secrets, enable CORS for the frontend domain, and set up health check endpoints for monitoring. Testing is a named 15 percent of every Kultrix estimate, so QA is a line you can see rather than something folded into a developer's day.

Yes. Strapi's plugin architecture allows extending the admin UI with custom panels, adding middleware, creating custom API routes, and registering lifecycle hooks. Kultrix has built plugins for custom approval workflows, third-party sync, and content audit logging. Kultrix quotes an AI feature dropped into a product that already ships at 180-420 hours, and the AI module itself at 150-340 hours.

It depends on the data. Server state (API data) is best managed with React Query or SWR. Global UI state works well with Zustand or Redux Toolkit. Local component state stays in useState and useReducer. We avoid over-engineering state management. Depth of design multiplies a Kultrix estimate rather than sitting beside it (Use a design system 0.85x, Custom design 1x, Signature visual identity 1.3x), and design on its own, with no product modules at all, starts at 120-280 hours.

We use React Hook Form for complex forms, it is performant, uncontrolled by default, and integrates cleanly with Zod for schema validation. For simple cases, controlled components with useState are sufficient. A Kultrix engagement is split the same way every time - 70 percent of the hours on design and development, 15 percent on QA and 15 percent on project management - and the team stops growing at the point where coordination eats the gain.

tRPC is a library that gives you end-to-end type safety between your TypeScript backend and frontend, no code generation, no OpenAPI schema, just shared types. It is ideal for Next.js full-stack projects where backend and frontend live in the same repo. Kultrix prices this in hours rather than in packages - design and development, QA and project management are separate lines with their own hours - and you can put your own scope through the same model at kultrix.com/cost-calculator.

Types are erased at runtime, so API inputs and external data need runtime validation. We use Zod, it lets you define schemas that both validate at runtime and infer TypeScript types, keeping a single source of truth. Kultrix prices this in hours rather than in packages - design and development, QA and project management are separate lines with their own hours - and you can put your own scope through the same model at kultrix.com/cost-calculator.

shadcn/ui is a collection of accessible, unstyled React components built on Radix UI primitives, styled with Tailwind CSS. Components are copied into your project, not installed as a dependency, giving full ownership and customization. Kultrix uses shadcn/ui as the baseline for Tailwind-based design systems. Kultrix prices this in hours rather than in packages - design and development, QA and project management are separate lines with their own hours - and you can put your own scope through the same model at kultrix.com/cost-calculator.

We use the class-based dark mode strategy, toggling a dark class on the root element via JavaScript. CSS variables for colors update based on the dark class, and Tailwind's dark: variant classes override light-mode styles. System preference detection with prefers-color-scheme is the default. Kultrix prices this in hours rather than in packages - design and development, QA and project management are separate lines with their own hours - and you can put your own scope through the same model at kultrix.com/cost-calculator.