Senior Backend Engineer — AI Observability & Evals

Applied Methods Ltd; New York (NY); Hybrid; USD 180,000 - 240,000; Full time

Benefits offered by this job

Medical coverage

Dental coverage

Vision coverage

401(k) plan

Meals on in-office days

Job summary

LangChain in NYC is seeking a Senior Backend Engineer to build and maintain the backend systems powering LangSmith’s observability and evals platform. You’ll work on core services for tracing, monitoring, and evaluation workflows, collaborating with frontend and product teams.

Candidates should have 5+ years of backend experience, Python or Go, and proven ability to design reliable data services, optimize performance, and operate scalable databases on AWS/GCP/Azure.

Qualifications

• 5+ years of backend engineering experience in complex products.
• Proficiency in Python or Go and API design.
• Experience with high-throughput systems and reliability.
• Strong database and cloud platform experience (Postgres, Redis, ClickHouse; AWS/GCP/Azure).

Responsibilities

• Design, develop, and maintain backend services and APIs for tracing, monitoring, and evaluation workflows.
• Collaborate on architectural decisions for performance and maintainability.
• Optimize storage and query performance for high-volume observability data.
• Ensure reliability via testing, monitoring, and alerting.
• Troubleshoot production issues and perform root-cause analysis.
• Create and maintain system documentation including design and API references.
• Work with full-stack engineers, PMs, and designers on rolling out features.

Skills

Backend languages (Python/Go)

API design

Observability

Performance optimization

Cloud platforms

Tools

PostgreSQL

Redis

ClickHouse

AWS

GCP

Azure

Job description

LangChain in NYC is seeking a Senior Backend Engineer to build and maintain the backend systems powering LangSmith’s observability and evals platform. You’ll work on core services for tracing, monitoring, and evaluation workflows, collaborating with frontend and product teams.

Candidates should have 5+ years of backend experience, Python or Go, and proven ability to design reliable data services, optimize performance, and operate scalable databases on AWS/GCP/Azure.