> DOU
senior
White LabelFrontend Engineer
format:Remotetype:Contractcompany:Outsource
javascripthtml/cssreactnext.jspwa
typescriptreduxzustandtanstack queryjestreact testing libraryplaywrightcypresswcagci/cdvercel
> full description
Senior Frontend Developer (React / Next.js / PWA)
Location: Remote (Poland or Ukraine) | Type: B2B contract, full-time | Openings: 3
About the role
We are looking for experienced Senior Frontend Developers to join a client project building a modern Progressive Web Application. You’ll work on a commercial product used in production, working closely with the client’s product and engineering teams. We want engineers who have shipped PWAs before, not just React apps.
What you’ll do
- Build and maintain high-performance, responsive frontend features using React and Next.js
- Design and implement PWA functionality: service workers, offline support, caching strategies, installability, and push notifications
- Optimize performance (Core Web Vitals, bundle size, rendering strategies such as SSR, SSG and ISR)
- Work with backend teams on API integration and data flow
- Take ownership of code quality through code reviews, testing, and technical decisions
- Talk directly with the client’s stakeholders in English
What we’re looking for
- 6+ years of professional frontend development experience
- Strong command of JavaScript (ES6+), HTML5, and CSS3
- Deep hands-on experience with React and Next.js in production
- Proven PWA expertise, with at least one commercial PWA project you can walk us through in detail
- Solid understanding of web performance, browser APIs, and responsive/mobile-first design
- Experience working on your own in remote, client-facing setups
- Very good spoken and written English (B2+/C1)
- References from previous commercial projects
Nice to have
- TypeScript
- State management experience (Redux, Zustand, React Query or similar)
- Testing experience (Jest, React Testing Library, Playwright/Cypress)
- Accessibility (WCAG) knowledge
- CI/CD and deployment experience (Vercel or similar)