LangChain
Senior Fullstack Software Engineer, AI Observability & Evals Platform (NY)
$175K–$240K
San Francisco, CA · On-site · Senior · Full-time · Posted Oct 8, 2026
- Experience
- 5+ years.
About the job
Lead fullstack engineering for LangSmith, an observability and evaluation platform, shaping its architecture and product features while collaborating with customers and internal teams.
What you'll do
- Lead the technical architecture and implementation of LangSmith product features across the Go, Python, and Typescript stack.
- Collaborate with product and design teams to develop and iterate on features; engage with enterprise customers and developer end-users.
- Mentor junior engineers and promote clean, maintainable, well-tested code while delivering projects to timelines.
What they ask for
- 5+ years of software engineering experience working on complex platform products.
- Fullstack experience with Go or Python on the backend and React + Typescript on the frontend.
- Strong understanding of database systems, particularly Postgres and Redis.
- Experience designing and scaling APIs.
Nice to have
- Experience with AI/LLM-powered applications, developer tools, or observability platforms.
Pay
$175,000-$240,000 USD (base salary)
Tools
Go, Python, Typescript, React, Postgres, Redis
AI focus
The role develops LangSmith, an AI observability and evaluation platform; experience with AI/LLM-powered applications is a bonus.
Model-written summary · the original posting is authoritative