Shape the technical direction of LangSmith, an observability and evals platform, as a Senior Fullstack Engineer.
Posted by employer 1 day ago
First seen on Joblaze 11 hours ago
Last verified on the company career page 11 hours ago
Skills & Technologies
What you'll build
- Lead technical architecture and implementation of product features
- Collaborate with product and design teams
- Mentor junior team members
- Write clean, maintainable, and well-tested code
Must have
- 5+ years of experience in software engineering
- Fullstack engineering experience with Go or Python and React + TypeScript
- Strong understanding of database systems, particularly PostgreSQL and Redis
- Experience designing and scaling APIs
Nice to have
- Experience with AI/LLM-powered applications
- Experience with developer tools
- Experience with observability platforms
Requirements
- Experience
- 5+ years
Not disclosed in this posting: work arrangement, visa sponsorship.
Benefits
Joblaze summary
In the role of Senior Fullstack Software Engineer at LangChain, the individual will lead the development of key features for the LangSmith observability and evaluation platform, engaging with both enterprise clients and internal teams. Proficiency in Go, Python, and Typescript is essential, along with a solid grasp of database systems like Postgres and Redis. This position is ideal for someone with over five years of experience in software engineering, particularly in complex platform products, who is comfortable mentoring junior engineers and driving projects forward. LangChain's growth stage and focus on AI technology provide a collaborative environment for impactful contributions.
Joblaze insights
- Listed today — first seen on Joblaze October 9, 2026. Last confirmed on LangChain's careers page October 9, 2026.
- Salary band is in line with the typical range for Fullstack roles (median ~$165,000).
- Starts above 64% of 107 comparable senior fullstack roles in United States that list React we track (median $167,000 across 52 companies). See React salary trends
- React appears in 68.6% of 242 comparable senior fullstack roles in United States; Redis appears in 6.6% of 242 comparable senior fullstack roles in United States.
Quick facts
- What's the salary range?
- LangChain lists $180,000–$240,000 for this role.
- How much experience is required?
- At least 5 years of relevant experience for this Senior Fullstack Software Engineer, AI Observability & Evals Platform (NY) role.
- What's the tech stack?
- Joblaze extracted these technologies from the posting: Go, PostgreSQL, Python, React, Redis, TypeScript.
- What seniority level is this role?
- LangChain targets senior candidates for this position.
- Is this full-time or contract?
- Full-time for this Senior Fullstack Software Engineer, AI Observability & Evals Platform (NY) role at LangChain.
From the original posting
About Us
About the role:
We're looking for a Senior Fullstack Engineer for our commercial product LangSmith, an observability and evals platform. In this role, you'll have the opportunity to shape the technical direction of our platform while working closely with enterprise customers, developer end-users and internal stakeholders.
What You Will Do:
Lead the technical architecture and implementation of key product features for LangSmith, working across our entire 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 are being met.
Lead by example in writing clean, maintainable, and well-tested code
What You Bring:
5+ 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 our top-tier customers
Strong ownership mindset
Bonus: Experience with AI/LLM-powered applications, developer tools, or observability platforms
Annual salary range: $180,000-$240,000 USD
Standard company text repeated across LangChain's postings is omitted here.