Senior Frontend Engineer (React/Next.js) — Remote

Zexter; Warszawa; Hybrid; PLN 180,000 - 260,000; Full time

Benefits offered by this job

Fully remote

Competitive salary

International team

Strong Dev & Product teams

Clear career path

Modern tools

Job summary

ZEXTER is seeking a Senior Frontend Developer to build and scale our in-house platform. You will own frontend development, shaping architecture and delivering production-grade frontend features using React, Next.js and TypeScript.

Join a fast-growing international iGaming-focused team with modern tooling and minimal bureaucracy, fully remote work, and opportunities to influence product quality and career growth.

Qualifications

• 5+ years of commercial frontend development, including 3+ years with React, owning and supporting production apps under real user load.
• Strong TypeScript skills: strict mode, generics, utility types, discriminated unions, and fully typed API contracts without any.
• Advanced React 18/19 & Next.js knowledge: hooks, render cycle, Suspense, Server/Client Components, App Router, SSR/SSG/ISR, middleware, caching and routing.
• Experience with TanStack Query, including query management, invalidation, SSR prefetching/hydration, persistent cache and optimistic updates.
• Ability to design and evolve large-scale frontend architecture: clear module boundaries, layered structure, public APIs, and gradual legacy migration without blocking feature development.
• Strong focus on code quality and testing: Vitest/Jest, React Testing Library, Playwright/Cypress, ESLint/Prettier, code reviews and Core Web Vitals optimization.
• Experience with modern frontend infrastructure and operations: Git, CI/CD (GitHub Actions/GitLab CI), Sentry, Docker and Node.js deployments.
• Solid understanding of API communication and web security: REST, WebSocket, authentication/refresh flows, CORS, CSP, XSS, SSRF and secure BFF patterns.
• Experience working in a cross-functional product team with backend, design and QA, plus hands-on knowledge of Tailwind CSS, Zod and internationalization (next-intl or equivalent).
• English, Russian - B2 mandatory!

Responsibilities

• Develop and maintain scalable, high-performance frontend applications using React, Next.js and TypeScript.
• Design and implement robust frontend solutions, contributing to architecture decisions and improving existing systems.
• Build and deliver end-to-end product features, collaborating closely with backend developers, QA, design and product.
• Ensure code quality, performance and reliability through testing, code reviews, monitoring and continuous optimization.
• Contribute to development processes and frontend best practices, improving tooling, CI/CD, observability and overall engineering quality.

Skills

5+ years frontend

3+ years React

TypeScript

Next.js

TanStack Query

Tailwind CSS

Testing (Vitest/Jest)

Tools

Git

CI/CD

Sentry

Docker

Node.js deployments

pnpm workspaces

Job description

ZEXTER is seeking a Senior Frontend Developer to build and scale our in-house platform. You will own frontend development, shaping architecture and delivering production-grade frontend features using React, Next.js and TypeScript.

Join a fast-growing international iGaming-focused team with modern tooling and minimal bureaucracy, fully remote work, and opportunities to influence product quality and career growth.