UI/UX Engineer

Phinomenon is built by browser and cloud veterans — our founders behind FydeOS (a Chromium-based OS trusted by millions) and QingCloud (one of China's earliest API-first IaaS platforms founded in 2012). Fresh off a healthy, eight‑figure Series A raise, we've got the cash runway one needs to dream big without panicking about next week's payroll. With folks working from San Francisco, London, Beijing, Shanghai and Shenzhen, we're proudly global and friendly to your time zone, with overlapping hours so we can all actually talk. We ship fast and ship hard — but burnout is so last decade, so we bake in wellness stipends, mandatory recharge days and flexible schedules, because great code comes from healthy lives. If you want to build the nextgen browser that actually, you know, gets you — while still enjoying your evenings and maintaining upright posture — welcome home.

As our UI/UX Engineer, you'll join forces with researchers and frontend teams to take wireframes and prototypes and turn them into interactive, polished, code-driven experiences. You're equally at home sketching user flows one moment and optimizing animations the next. Your mission: create seamless, user-centric interfaces that are both pixel-perfect and powerful.

• Partner with design and research to define usability goals, sketch flows, and assess technical feasibility
• Convert high-fidelity mockups into responsive, production-ready UI components using modern frontend tech (React/TS/CSS)
• Build and maintain design systems — component libraries, style guides, tokens — for consistency across platforms
• Prototype interactive features, animations, transitions, and microinteractions to elevate UX
• Conduct UI-level testing, usability validation, and iterate based on feedback
• Debug and optimize for performance, accessibility (WCAG), and cross-browser/device support
• Mentor peers on design-system best practices and code craftsmanship

• 3+ years experience in frontend development with a strong eye for design
• Experience building and maintaining design systems or component libraries
• Solid understanding of UX principles: wireframing, prototyping, user flows, HCI
• Comfortable working with engineers in a fast-paced, iterative process
• Familiarity with testing tools (unit/UI/accessible test frameworks) and performance profiling
• Excellent communicator, able to translate design intent into code clearly and collaboratively

• Experience with Figma, Sketch, or Adobe XD for handoff workflows
• Proficiency in motion/UI animation libraries (Framer Motion, Lottie)
• Understanding of AI-assisted design tools and generative UI concepts
• Knowledge of accessibility standards and tooling (WCAG, ARIA)
• Contributions to open-source frontend or UX tooling/projects