Senior Frontend Platform Engineer, Design Systems

LangChain; United States; Remote; USD 130,000 - 180,000; Full time

Job summary

LangChain is seeking a Design Systems Engineer to build and evolve a scalable component library that powers LangChain’s frontend products. You will collaborate with designers and platform teams to translate design intent into robust, reusable components and tooling that ensure accessibility, performance, and visual consistency across the UI stack.

You’ll own design system tooling, theming, and token workflows, contributing to faster iteration and higher quality experiences across LangChain’s

Qualifications

• Strong experience building scalable design systems and reusable UI components.
• Proficient in React and modern frontend tooling, with a focus on accessibility and performance.
• Experience translating design systems into production-ready code using tokens, components, and stories.

Responsibilities

• Build out LangChain’s component library and design system assets.
• Create reusable, accessible React components that scale across products.
• Collaborate with designers to translate tokens and interaction patterns into code.
• Develop and maintain design system tooling, theming, and versioning workflows (e.g. Storybook).
• Contribute to performance optimization, testing, and UX consistency across the UI stack.
• Improve build/test workflows and package/versioning strategies.
• Partner with platform teams to ensure alignment with product goals.

Skills

React

Design Systems

Accessibility

UI development

Storybook

Component libraries

Tools

Storybook

Design Tokens

NPM/Yarn

CI/CD

Job description

About Us

At LangChain, our mission is to make intelligent agents ubiquitous. We build the foundation for agent engineering in the real world, helping developers move from prototypes to production-ready AI agents that teams can rely on. We began as widely adopted open-source tools and have grown to also offer a platform for building, evaluating, deploying, and operating agents at scale.With $125M raised at Series B from IVP, Sequoia, Benchmark, CapitalG, and Sapphire Ventures, we’re at a stage where we’re continuing to develop new products, growth is accelerating, and all team members have meaningful impact on what we build and how we work together. LangChain is a place where your contributions can shape how this technology shows up in the real world.Today, our platform includes LangSmith (Observability, Evaluation, Deployment, Fleet, and Sandboxes), our open source frameworks (LangChain, LangGraph, and Deep Agents), and the newly launched LangSmith Engine for autonomous agent improvement. We have 100M+ monthly open source downloads, 6,000+ active LangSmith customers, and 5 of the Fortune 10 use LangSmith in production (+ 35% of the Fortune 500 overall), including teams at Klarna, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, LinkedIn, Monday.com, Nvidia, and Bridgewater.

About the Role:

This role can be based remotely in the U.S. Ideally SF, NYC, or Boston.LangChain 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 LangChain’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 LangChain’s products.

What You’ll Do:

• Build out LangChain’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 LangChain’s UI stack
• Improve UI build and test workflows
• Optimize build performance, bundling strategy, and package versionin