Frontend UI Engineer

Quick Facts

• Role: Frontend/UI Engineer
• Location: Warsaw (Hybrid)
• Work model: 5 days in office

Role Description

Build and maintain a large-scale React-based component library that serves as the shared design system and UI foundation for web applications. You will design and ship production UI components with comprehensive test coverage and strict WCAG accessibility compliance, while debugging issues across components, theming/styling, and build tooling. The role also uses AI coding agents (such as Claude Code) daily to scale UI workflows and improve internal agent tooling.

Responsibilities

• Build and maintain a large-scale React-based component library and shared design system
• Design and ship production UI components with high consistency
• Ensure comprehensive test coverage and strict accessibility compliance (WCAG)
• Diagnose and resolve bugs across the component library, theming/styling layer, and build tooling
• Collaborate with design and platform teams to meet design-system and performance standards
• Use AI coding agents (e.g., Claude Code) to scale AI-driven workflows
• Design and implement UI-related agent skills; improve internal tooling

Requirements

• Proven experience building UIs, component libraries, and/or design systems at scale
• Strong knowledge of React and TypeScript (with basic familiarity with Angular for maintenance)
• Solid experience with CSS-in-JS and Sass
• Deep understanding of WCAG and hands-on experience building accessible components
• Experience with React Testing Library and Cypress
• Experience with build/monorepo tooling (Bazel)
• Hands-on experience with Claude Code (or equivalent agentic coding CLI), directing AI agents in large codebases
• Ability to actively evaluate and improve AI-agent workflows (prompts, skills, guardrails)