Senior Frontend developer (Next,React,TypeScript) (#4118)

Our client is one of Europe's fastest-growing mobile companies with 5 million active customers, 1,000 employees worldwide, and operations in five countries. The client is using the mobile virtual network operator business model.

We are looking for a Senior Front End result-oriented developer who has good knowledge and experience of Next.js, TypeScript and React.

Responsibilities

• Build high-impact Next.js features: apply ISR, SSR, SSG, route segment config, middleware, and edge functions to balance performance, freshness, and SEO.
• Own a design library: create accessible, themeable primitives (tokens, typography, spacing, color) and higher-level components; publish as a versioned package for multiple apps.
• Heavy shadcn/ui usage: extend and harden shadcn components; extract shared primitives; align with design tokens and Tailwind; enforce accessibility (ARIA) and robust API surfaces.
• Microfrontends at scale: design integration boundaries (routing, shared deps, contracts); use Module Federation or package-based composition/monorepo tooling; manage versioning and changelogs.
• State management: choose the right tool per scope—React Query/TanStack Query, Redux Toolkit, Zustand/Jotai, or RSC/server actions—while minimizing client state.
• Storybook-first delivery: document components with MDX; set up controls, a11y tests, interaction tests, and (optionally) visual regression.
• Performance & UX polish: optimize web vitals (LCP/CLS/INP), code-split routes, tune caching headers, image optimization, and streaming UI; add robust error/fallback states.
• Containerized dev: craft efficient multi-stage Docker images; run full app + deps via docker-compose; contribute to CI checks and preview environments.
• Quality & reliability: write unit/integration/e2e tests (Testing Library, Jest/Vitest, Playwright/Cypress); enforce lint/type rules; add feature flags and telemetry (logs/metrics/errors).
• Cross-functional collaboration: partner with design on Figma handoff, review PRs, lead design docs/tech spikes, and mentor other engineers.

Requirements

• 5+ years building production web UIs; 3+ years with Next.js + TypeScript.
• Deep knowledge of ISR/SSR/SSG, App Router, RSC, server actions, caching strategies, and SEO fundamentals.
• Proven experience shipping and maintaining a component library/design system (tokens, theming, versioning, changelogs).
• Significant hands-on work with shadcn/ui and Tailwind, extending components and creating custom, accessible primitives.
• Comfortable with microfrontends: architecture, Module Federation (or package-based MFE), shared dependency strategy, and release workflows.
• Strong Docker and docker-compose skills for local dev and service integration.
• Solid testing practice across unit/integration.
• Performance mindset with practical web-vitals tuning and profiling.
• Excellent communication, ownership, and mentorship.

Nice to have

• Experience with monorepos (Nx/Turborepo), package publishing, and semver discipline.
• Analytics/experimentation (A/B testing), feature flags, and progressive rollout.
• Familiarity with headless CMS/e-commerce, and API design (REST).