Full Stack Engineer, Observability & Evals Platform (LangSmith)

About LangChain

At LangChain, our mission is to make intelligent agents ubiquitous. We help developers build mission-critical AI applications across the entire agent development lifecycle. Our open source frameworks — LangChain and LangGraph — see over 70+ million downloads per month. Developers rely on LangChain for composable integrations and LangGraph for controllable agent orchestration. Our commercial agent platform, consisting of LangSmith and LangGraph Platform, enables teams to build, test, run, and manage agents at scale across their organization.

Founded in 2023, LangChain powers top engineering teams at companies like Replit, Lovable, Clay, Klarna, LinkedIn, and more.

About the role:

In person 5 days/week in San Francisco

We're looking for a Full Stack Engineer to work on LangSmith, our commercial observability and evals platform product. In this role, you'll have the opportunity to build new features and functionality for the platform while working close enterprise customers, developer end-users and internal stakeholders.

• Develop and implement key product features working across our entire Go, Python, and Typescript stack

• Collaborate closely with product and design teams to iterate on new features and enhance the product roadmap

• Drive aggressive project timelines while ensuring high engineering standards are being met by writing clean, maintainable, and well-tested code

How to be successful in this role

• 2+ years of experience in software engineering working on complex platform products

• Fullstack engineering experience with Go or Python on the backend and React + Typescript on the frontend

• Solid understanding of database systems, particularly Postgres and Redis

• Experience designing and scaling APIs, preferably in high-performance, data-intensive applications

• A “get stuff done” attitude - comfortable shipping fast and iterating based on user feedback

• Strong communicator with the ability to collaborate closely with various internal stakeholders and engage directly with our top-tier customers

• Strong ownership mindset

• Bonus: Experience with AI/LLM-powered applications, developer tools, or observability platforms

Compensation & Benefits

• Competitive salary and equity stake for role and stage of company. Commensurate with experience.

• Annual salary range: $140,000-175,000 USD