Frontend Platform Engineer, Design Systems — United States

About the Company

LangChain builds tools and infrastructure that help developers create, evaluate, deploy, and operate reliable AI agents in production. Its platform includes LangSmith, an observability, evaluation, deployment, fleet, and sandbox platform, alongside open-source frameworks such as LangChain, LangGraph, and Deep Agents.

The company has raised $125 million in Series B funding from IVP, Sequoia, Benchmark, CapitalG, and Sapphire Ventures. Its open-source tools receive more than 100 million monthly downloads, and LangSmith serves over 6,000 active customers. Five of the Fortune 10 companies use LangSmith in production, along with more than 35% of the Fortune 500.

About the Role

LangChain is seeking a Design Systems Engineer to build, maintain, and evolve its component library, which provides the foundation for consistent, accessible, and high-quality user interfaces across its products.

In this role, you will work at the intersection of design and engineering, collaborating with designers, product engineers, and platform teams to turn design concepts, tokens, and interaction patterns into reusable, production-ready components and tools. You will help frontend teams deliver products efficiently while maintaining quality, accessibility, and consistency. Your work will directly support LangChain's products and UI ecosystem.

This position can be based remotely within the United States, with San Francisco, New York City, or Boston preferred.

Key Responsibilities

• Build and maintain LangChain's reusable component library.

• Design and implement flexible, composable, accessible, and production-ready React components.

• Collaborate with designers to translate design systems, tokens, and interaction patterns into code.

• Develop design system tooling and improve workflows for theming, tokens, versioning, testing, and component discovery, including tools such as Storybook.

• Make architectural decisions that support accessibility, performance, consistency, and maintainability across the UI stack.

• Improve UI build and testing workflows.

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

• Maintain tooling for UI component testing and dependency management.

Required Qualifications

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

• Deep knowledge of React, TypeScript, HTML, and CSS.

• Familiarity with styling approaches such as CSS Modules, CSS-in-JS, Tailwind, and Sass.

• Familiarity with design system tools and workflows, including Storybook, Chromatic, and design token pipelines.

• Experience collaborating closely with designers and non-engineering partners.

• Strong attention to detail and a high standard of craftsmanship.

• Genuine interest in accessibility and inclusive design.

• Familiarity with UI component testing and visual regression testing.

Compensation & Benefits

• Annual salary range: $180,000–$240,000.

• Compensation may include base salary, variable compensation for relevant roles, meaningful equity, benefits, and additional perks. The final offer will depend on the candidate's demonstrated impact, craft, leadership, and communication during the interview process. LangChain discusses compensation expectations early in the hiring process and before the offer stage.

• Benefits include medical, dental, and vision coverage, flexible vacation, a 401(k) plan, and meals on in-office days in the United States. Team members in the EU, UK, and APAC receive locally competitive benefits aligned with regional norms and regulations.