Senior Front-End Engineer

Proxima•New York, NY

32d•$150,000 - $190,000•Hybrid

About The Position

Proxima has a unique dataset most companies only dream of: real-time, anonymized cross-brand transaction data at scale. We're looking for a Senior Frontend Engineer to join our team building AI-driven products powered by this data to help level the playing field, helping independent brands find their perfect customers while helping consumers discover their next favorite products from businesses they've never heard of. You'll be responsible for crafting exceptional user experiences, from designing intuitive AI agent interfaces to building responsive web applications that make complex data insights accessible and delightful. This role is ideal for front-end specialists who obsess over pixel-perfect designs, smooth interactions, and performant web applications. If you thrive in fast-paced, startup environments and love pushing the limits of modern frontend development with AI assistance, we want to talk to you.

Requirements

6+ years of professional frontend development experience
Bachelor's degree (or higher) in Computer Science, Engineering, Design, or a related field
Proven experience working in startup environmentsâyou've shipped products fast and worn multiple hats
Expert-level proficiency with TypeScript and React (including hooks, context, and modern patterns), with a strong ability to design maintainable, strongly-typed APIs
Strong command of CSS/SCSS, including Flexbox, Grid, animations, and responsive design techniques
Experience with modern frontend tooling (Webpack, Vite, ESBuild, etc.)
Solid understanding of web performance optimization and browser APIs
Experience building interfaces for AI-powered applications or complex data-driven products
Daily use of AI-assisted coding tools (e.g., GitHub Copilot, Cursor, Claude Code, etc.) is a requirement
Comfortable owning projects independently in a high-velocity development environment

Nice To Haves

Experience with state management libraries (Redux, Zustand, Jotai, etc.)
Familiarity with design systems and component library development (Storybook, Radix, shadcn/ui, etc.)
Knowledge of data visualization libraries (D3.js, Recharts, Plotly, etc.)
Experience with frontend testing frameworks (Jest, Vitest, Playwright, Cypress)
Understanding of accessibility standards (WCAG) and inclusive design principles
Background in UX/UI design or strong design sensibility

Responsibilities

Build, maintain, and scale frontend applications using TypeScript and React
Design and implement user interfaces for AI agent interactions, data visualizations, and consumer-facing products
Write clean, maintainable, and semantic HTML/CSS/SCSS with a strong eye for design and UX
Create responsive, accessible, and performant web applications that work flawlessly across devices and browsers
Collaborate closely with product and designers to translate mockups and prototypes into production-ready code
Build reusable component libraries and design systems
Optimize frontend performance, including bundle sizes, load times, and runtime efficiency
Work with backend teams to integrate APIs and manage application state effectively
Own frontend architecture decisions and champion best practices across the team
Stay on the cutting edge of modern frontend development, especially around AI-powered user experiences