Frontend Platform Engineer, Design Systems

About Lang Chain

At Lang Chain, our mission is to make intelligent agents ubiquitous. We provide the agent engineering platform and open source frameworks developers need to ship reliable agents fast.

Our open source frameworks, Lang Chain and Lang Graph, see over 90+ million downloads per month and help developers build agents with speed and granular control. Lang Smith offers observability, evaluation, and deployment for rapid iteration, enabling teams to transform LLM systems into dependable production experiences.

Lang Chain is trusted by millions of developers worldwide and powers AI teams at companies like Clay, Cloudflare, Harvey, Rippling, Vanta, Workday, and more.

Lang Chain is building the infrastructure that powers the next generation of AI applications. Our tools are used by thousands of developers and teams to build, debug, and ship production-grade LLM-powered products.

As our product surface area grows, so does the need for a cohesive, scalable, and high-quality UI foundation
. That’s where Design Systems comes in. We’re looking for a Design Systems Engineer to help build, own, and evolve Lang Chain’s component library
—the foundation that our frontend teams rely on to ship fast without sacrificing quality, accessibility, or consistency.

This role sits at the intersection of Design and Engineering
. You’ll work closely with designers, product engineers, and platform teams to turn design intent into robust, reusable components and tooling that scale across the product.

You’ll have ownership, influence, and your work will be directly consumed across Lang Chain’s products.

• Build and own Lang Chain’s component library

  • Design and implement reusable, composable React components that are flexible, accessible, and production-ready

  • Partner closely with designers to translate design systems, tokens, and interaction patterns into code

• Build reliable UI quality systems

  • Develop design system tooling and improve workflows around theming, tokens, versioning, testing, and component discovery (e.g. Storybook)

  • Make thoughtful architectural decisions that enable accessibility, performance, consistency, and maintainability across Lang Chain’s UI stack

• Improve UI build and test workflows

  • Optimize build performance, bundling strategy, and package versioning for the component library

  • Maintain tooling for testing, dependency management of the UI app

• Strong experience building modular, composable, and well-documented component libraries and/or design systems

• Deep knowledge of React, Type Script, HTML, and CSS
  , familiarity with: styling approaches (CSS Modules, CSS-in-JS, Tailwind, Sass, etc.) and design system toolings (Storybook, Chromatic, tokens pipelines, etc.)

• Experience collaborating closely with designers and non-engineering partners

• Strong attention to detail and a high bar for craft and genuine passion for accessibility and inclusive design

• Familiarity with testing UI components and visual regression testing

Compensation: We offer competitive compensation that includes base salary, meaningful equity, and benefits such as health and dental coverage, flexible vacation, a 401(k) plan, and life insurance. Actual compensation will vary based on role, level, and location. For team members in the EU and UK, we provide locally competitive benefits aligned with regional norms and regulations. Annual salary range: $170,000 - $195,000