Senior Frontend Engineer – React/Next.js UI Lead

flyer-one-ventures; Warszawa; On-site; PLN 210,000 - 320,000; Full time

Job summary

flyer-one-ventures in Warszawa, Poland, is seeking a senior software engineer to own the design and maintenance of web applications. The role focuses on TypeScript, React, Next.js, and React Query, with a fast-paced environment and minimal technical debt.

You will translate Figma mockups into polished, accessible UIs, drive architecture, optimize Core Web Vitals, and collaborate with design and product leadership to deliver delightful experiences.

Qualifications

• 5+ years of experience as a software engineer.
• 3+ years building and shipping web apps with React and Next.js.
• Strong knowledge of TypeScript, React, and React Native.
• Experience turning Figma mocks into websites.
• Solid UI/UX design understanding and attention to visual detail.
• Experience polishing UI with a designer collaboration.
• Experience with testing frameworks (Jest, Detox, etc.).

Responsibilities

• Own the technical vision and architecture for web applications.
• Lead end-to-end development of new user-facing features.
• Turn fuzzy ideas into clear specs and roadmaps.
• Build intuitive, responsive UIs from Figma mocks.
• Optimize performance focusing on Core Web Vitals.
• Evolve React/Next.js structure including routing and state.
• Define React Query caching, retries, and optimistic updates.
• Build a cross-platform component library with Storybook.
• Collaborate with design and product leadership to shape the experience.
• Represent engineering in roadmap discussions, balancing value and risk.
• Prototype UI/UX quickly to de-risk big bets with design.

Skills

Senior software engineer

React

Next.js

TypeScript

UI/UX

Tools

Jest

Detox

Storybook

Job description

flyer-one-ventures in Warszawa, Poland, is seeking a senior software engineer to own the design and maintenance of web applications. The role focuses on TypeScript, React, Next.js, and React Query, with a fast-paced environment and minimal technical debt.

You will translate Figma mockups into polished, accessible UIs, drive architecture, optimize Core Web Vitals, and collaborate with design and product leadership to deliver delightful experiences.