Senior Fullstack Engineer, AI Observability & Evals Platform

Langchain·Boston, MA·Posted 12 September 2026

Apply with a tailored CV View on Langchain's site

About the role

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. 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. Today, our platform includes LangSmith (Observability, Evaluation, Deployment, Fleet, and Sandboxes), our open source frameworks (LangChain, LangGraph, and Deep Agents), and the newly launched LangSmith Engine for autonomous agent improvement. We have 100M+ monthly open source downloads, 6,000+ active LangSmith customers, and 5 of the Fortune 10 use LangSmith in production (+ 35% of the Fortune 500 overall), including teams at…

This is a summary of the advert. The full description and the application are on Langchain's careers site.

Apply faster with Prepper

A version of your CV tailored to this Senior Fullstack Engineer, AI Observability & Evals Platform role.
A cover letter written from your CV and this advert.
Prepper can fill in Langchain's application form and send it once you approve.
The application saved in your tracker, with reminders to follow up.

Start free

More roles at Langchain

Prepper is independent and not affiliated with Langchain. Roles are listed from the employer's public careers system and removed when they close.