Backend Engineer, Observability & Evals Platform (LangSmith)
LangChain is seeking a Backend Engineer to join the LangSmith team, focusing on designing and building backend systems for their observability and evaluation platform. This role involves developing core services for monitoring and evaluating AI applications at scale, ensuring system performance, reliability, and maintainability.
At LangChain, 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, LangChain and LangGraph, see over 90+ million downloads per month and help developers build agents with speed and granular control. LangSmith offers observability, evaluation, and deployment for rapid iteration, enabling teams to transform LLM systems into dependable production experiences.
LangChain is trusted by millions of developers worldwide and powers AI teams at companies like Replit, Clay, Cloudflare, Harvey, Rippling, Vanta, Workday, and more.
We are looking for a Backend Engineer to join our LangSmith team. In this role, you will be responsible for designing and building the backend systems that power LangChain’s observability and evals platform. You will work on the core services that allow developers to monitor and evaluate their AI applications at scale. While the focus is on backend feature development, familiarity with fullstack or frontend engineering, performance tuning, and debugging production issues would be extremely valuable.
This role is based in our San Francisco, New York, or Boston office. Employees within commuting distance work from the office five days per week. Candidates who live outside commuting distance (e.g. >1hr each way), may be eligible for hybrid arrangements depending on location and role requirements.
Posted June 8, 2026