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

Work type : Office / Remote Technical Level : Senior Job Category : Software Development Project : Lebara

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

Nice to have

We offer