Frontend Engineer, AI Observability & Evals Platform

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.Today, LangChain, LangGraph, LangSmith, and Agent Builder are used by teams shipping real AI products across startups and large enterprises. Millions of developers trust LangChain to power AI teams at companies like Replit, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, and 35% of the Fortune 500.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.About the role: In person 5 days/week in San Francisco, CA, New York, Boston, London, or AmsterdamWe’re looking to add a frontend engineer to develop and enhance new features on LangSmith, working on our enterprise platform product for LLM application observability, testing, and debugging. You will: Develop new user-facing features using React & TypescriptBuild reusable components and front-end libraries for future useTranslate designs and wireframes into high-quality codeOptimize components for maximum performance across a vast array of web-capable devices and browsersCollaborate with fullstack and backend developers and UX/UI designers, to enhance usabilityIn this role, you’re a good fit if you have:Front-end engineering experience with strong proficiency in React, JavaScript and TypeScriptHands-on experience with front-end development tools like Babel, Vite, Webpack, NPM, and YarnFamiliarity with REST APIs and experience working closely with fullstack and backend engineersKnowledge of modern authorization mechanisms, such as JWTsA passion for user experience, design and building clean, engaging, and intuitive interfacesStrong written and oral communication skills, with the ability to explain technical concepts clearly and concisely to both technical and non-technical stakeholdersThe DNA to thrive in a start-up, fast-paced environment. Views unstructured environments as an opportunity to figure out the most impactful work and help define the future success of the companyAn ownership mind-set. You are self-driven and look for opportunities to make an impact.Strong computer science fundamentals, ideally with a degree in computer science or related fieldCompensation & Benefits:We offer competitive compensation that includes base salary, variable compensation for relevant roles, meaningful equity, benefits, and perks. Benefits include things like medical, dental, and vision coverage, flexible vacation, a 401(k) plan, and life insurance. Actual compensation and offerings will vary based on role, level, and location. Team members in the EU, UK, and APAC receive locally competitive benefits aligned with regional norms and regulations.Annual salary range: $155,000-$195,000 USD