Frontend Engineer, AI Observability & Evals Platform

LangChain· Engineering

San Francisco, CA, Boston, MA, New York, NY$160k - $195kFull-timePosted 8mo ago

About the role

Frontend engineer to develop and enhance features on LangSmith, LangChain’s enterprise platform for LLM observability, testing, and debugging.

Develop new user-facing features using React & Typescript
Build reusable components and front-end libraries for future use
Translate designs and wireframes into high-quality code
Optimize components for maximum performance across a vast array of web-capable devices and browsers
Collaborate with fullstack and backend developers and UX/UI designers, to enhance usability

2+ years of Front-end engineering experience with strong proficiency in React, JavaScript and TypeScript
Hands-on experience with front-end development tools like Babel, Vite, Webpack, NPM, and Yarn
Familiarity with REST APIs and experience working closely with fullstack and backend engineers
Knowledge of modern authorization mechanisms, such as JWTs
A passion for user experience, design and building clean, engaging, and intuitive interfaces
Strong written and oral communication skills, with the ability to explain technical concepts clearly and concisely to both technical and non-technical stakeholders
The 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 company
An 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 field

Required:ReactTypeScriptJavaScriptREST APIsCommunication

Nice to have:JWT

Last updated Oct 14, 2026. Interested? Apply on the company site.

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