LangChain

AI

PrincipalSoftwareEngineer,AIObservability&EvalsPlatform

$230–270k Boston, Massachusetts, United States FULL TIME Remote Friendly
Market Sentiment
HIGH DEMAND

Neural analysis suggests this role is
optimal for Principal candidates.

The Brief

“Principal Software Engineer, AI Observability & Evals Platform at LangChain. Skills: AI Observability, Evaluation Platform, Production Reliability, System Architecture, Mentoring Engineers. Lead architectural decisions across our Go, Python, and TypeScript stack. Work across the full stack, owning features end-to-end from backend services and APIs through to frontend product experiences”

What You'll Achieve.

Ensure systems are performant, maintainable, and built to scale; Optimize for performance and reliability; Keep systems running well at scale; Raise the technical quality of a team

Industry & Context.

AI
Problems you'll solve

Troubleshoot and resolve production issues; Root-cause mindset

What They're Looking For.

Must Have

10+ years of professional experience in backend or fullstack engineering on highly complex, production systems, programming skills across multiple parts of the stack: backend (Python and/or Go) and frontend (TypeScript, React, or similar), Demonstrated experience making and owning architectural decisions, including tradeoffs around data systems, APIs, and service reliability, Experience with high-throughput or mission-critical systems, and a proven ability to optimize for performance and reliability, Depth in operationalizing technical work — you've taken systems from prototype to production and kept them running well at scale, Demonstrated track record of mentoring engineers and raising the technical quality of a team, not just the codebase, communication skills and comfort operating cross-functionally with product, design, and engineering leadership, Customer centricity and an ownership mentality — you care how the product lands, not just how the code reads

Nice to Have

Experience with database systems (Postgres, Redis, ClickHouse), Experience with cloud platforms (AWS, GCP, or Azure), Familiarity with observability tooling, evaluation frameworks, or AI/LLM infrastructure

What You'll Do.

Lead architectural decisions across our Go

Work across the full stack

owning features end-to-end from backend services and APIs through to frontend product experiences

and evaluation workflows at scale

with a focus on reliability and query performance across high-volume data

Help shape the product roadmap by partnering closely with product and design

Set engineering standards for the team: define patterns

and establish the foundations others build on

Mentor and grow engineers at all levels through code review

and ongoing technical guidance

Drive projects from ambiguity to delivery while maintaining high engineering standards and aggressive timelines

Troubleshoot and resolve production issues with a root-cause mindset

and implement durable fixes

Ensure system reliability through testing

and alerting practices

Create and maintain technical documentation

including system design docs and API references

How You'll Work.

Team & Collaboration

Partnering closely with product and design; Comfort operating cross-functionally with product, design, and engineering leadership; Code review; Design feedback; Pairing

Communication Scope

Communication skills; Comfort operating cross-functionally

Process & Methodology

Drive projects from ambiguity to delivery, Maintaining aggressive timelines

Full Job Description

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, LangChain, LangGraph, LangSmith, and Fleet are used by teams shipping real AI products across startups and large enterprises. Millions of developers trust LangChain to power AI teams at companies like Replit, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, and 35% of the Fortune 500. ABOUT THE TEAM The LangSmith team owns and builds LangChain's core platform for observability, evaluation, and production reliability of AI systems. From tracing and annotation to run rules, evaluations, and beyond, they own this end-to-end. If you want to help define what great AI observability looks like at production scale, this is where that work gets done. ABOUT THE ROLE We're looking for a Principal/Lead level Software Engineer to join the LangSmith team and help drive the technical direction of the platform. You'll build across the full stack from backend services and APIs to frontend product surfaces, and you'll play a central role in shaping how we build: setting engineering standards, mentoring engineers across the team, and making architectural decisions that hold up as we scale. If you're energized by both hands-on engineering and the multiplier effect of leveling up those around you, this role is bui

Free ATS check

Applying for this Principal Software Engineer, AI Observability & Evals Platform role?

Most applicants get filtered before a human reads their resume. See if yours makes the cut.

How to Apply on Ashby

  • Ashby is a fast modern ATS — most applications take under 3 minutes.
  • The resume parser is strong; verify parsed experience dates and job titles.
  • Custom screening questions are often scored algorithmically — answer completely.
  • Location field affects geo-based screening; use your actual metro area.

ANONYMOUS · UNFILTERED

What do employees actually say about LangChain?

Real rants from real employees. Read before you apply.

Read Company Rants →