Senior Frontend Engineer: Design Systems & AI-Ready

JoinStartup; San Francisco, New York, Portland (CA, NY, OR); Hybrid; USD 201,000 - 251,000; Full time

Job summary

Mercury Technologies is seeking a Senior Frontend Engineer to design and maintain scalable design systems and component libraries. You will focus on AI-ready patterns, accessibility, and developer experience, building foundations that power all Mercury products.

You will mentor teammates, lead UI pattern initiatives, and shape prototyping workflows for rapid iteration in a fast-paced fintech environment.

Qualifications

• 7+ years of frontend development, with deep experience in React, TypeScript, and modern web technologies.
• Experience building or maintaining a design system or shared component library.
• A thorough command of modern frontend tooling: build systems, CI/CD, and testing.
• High agency, and comfort creating clarity in ambiguous spaces.
• Hands-on fluency at the intersection of AI and software development.

Responsibilities

• Build and maintain the components, patterns, and foundations (tokens, type, color, layout) with high accessibility and performance.
• Lead projects shipping new UI patterns to solve real pain points for product teams.
• Develop design system ready for AI integration and agent-assisted development.
• Invest in design system prototyping and rapid iteration capabilities.
• Mentor team members and establish best practices around design systems and AI fluency.

Skills

React

TypeScript

Frontend Development

Design Systems

Component Libraries

Web Accessibility

CSS/Styling

Build Systems

CI/CD

Testing

AI/ML Integration

Prototyping

Performance Optimization

Job description

Mercury Technologies is seeking a Senior Frontend Engineer to design and maintain scalable design systems and component libraries. You will focus on AI-ready patterns, accessibility, and developer experience, building foundations that power all Mercury products.

You will mentor teammates, lead UI pattern initiatives, and shape prototyping workflows for rapid iteration in a fast-paced fintech environment.