Principal AI Observability & Evaluation Platform Lead

LangChain; Cambridge (MA); On-site; USD 230,000 - 270,000; Full time

Benefits offered by this job

Medical, dental, and vision coverage

401(k) plan with company match

Meals on in-office days (US)

Job summary

LangChain is seeking a Principal/Lead Software Engineer to join the LangSmith team and drive the technical direction of the platform. You’ll build across the full stack—from backend services and APIs to frontend product surfaces—and mentor engineers while setting engineering standards for scale.

The role can be based in our Boston, San Francisco, or NYC offices, emphasizing hands-on coding, architecture, and cross-functional collaboration to elevate observability, evaluation, and reliability at

Qualifications

• 10+ years of professional backend or full‑stack engineering in production systems.
• Strong programming skills across backend (Python and/or Go) and frontend (TypeScript/React).
• Demonstrated experience making architectural decisions and ensuring reliability at scale.
• Proven ability to mentor engineers and raise the technical quality of a team.

Responsibilities

• Lead architectural decisions across Go, Python, and TypeScript stack.
• Own features end-to-end from backend services and APIs through to frontend product experiences.
• Mentor engineers and raise the technical quality of a team.
• Drive reliability through testing, monitoring, and documentation.

Skills

Backend engineering (Python/Go)

Frontend engineering (TypeScript/React

System design & architecture

Observability & reliability

Mentoring engineers

Cross-functional collaboration

Tools

PostgreSQL

Redis

ClickHouse

AWS

GCP

Azure

Job description

LangChain is seeking a Principal/Lead Software Engineer to join the LangSmith team and drive the technical direction of the platform. You’ll build across the full stack—from backend services and APIs to frontend product surfaces—and mentor engineers while setting engineering standards for scale.

The role can be based in our Boston, San Francisco, or NYC offices, emphasizing hands-on coding, architecture, and cross-functional collaboration to elevate observability, evaluation, and reliability at