# Senior Fullstack Engineer, AI Observability & Evals Platform

**Company:** [LangChain](https://hotfix.jobs/companies/langchain)
**Location:** New York, NY, Cambridge, MA, San Francisco, CA
**Role:** Fullstack Engineering
**Salary:** $175k – $225k/yr
**Experience:** 7+ years
**Skills:** Go, Python, TypeScript, React, Postgres, Redis, APIs
**Posted:** 2025-02-19

> Senior Fullstack Engineer leads architecture and implementation of observability platform features using Go/Python backend and React/TypeScript frontend. Requires 7+ years experience, database expertise (Postgres/Redis), and API scaling skills; onsite in SF with enterprise collaboration.

## Job Description

## Responsibilities
- Lead the technical architecture and implementation of key product features for LangSmith, working across Go, Python, and Typescript stack.
- Collaborate closely with product and design teams to iterate on new features.
- Mentor and guide more junior members of the team.
- Drive aggressive project timelines while ensuring high engineering standards.
- Lead by example in writing clean, maintainable, and well-tested code.

## Requirements
- 7+ years of experience in software engineering working on complex platform products.
- Fullstack engineering 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, preferably in a high-performance, data-intensive application.
- A “get stuff done” attitude - comfortable shipping fast and iterating based on user feedback.
- Strong communicator with the ability to collaborate closely with various internal stakeholders and engage directly with top-tier customers.
- Strong ownership mindset.

## Nice-to-Haves
- Experience with AI/LLM-powered applications, developer tools, or observability platforms.

## Compensation
- Annual salary range: **$175,000-$225,000 USD**
- Meaningful equity, health and dental coverage, flexible vacation, 401(k) plan, and life insurance.

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**Canonical:** https://hotfix.jobs/jobs/361781a1-b795-4e2d-80e7-3d267fb4d412