Senior Fullstack Engineer, AI Observability & Evals Platform
About this role
Writing clean, maintainable, and well-tested code forms the core of daily responsibilities while shaping the technical direction of the LangSmith platform. The engineering team owns LangChain's core platform for observability, evaluation, and production reliability, handling everything from tracing and annotation to run rules and evaluations.
Engineers joining this group collaborate closely with product and design teams, enterprise customers, developer end-users, and cross-functional internal stakeholders. Ideal candidates bring a strong ownership mindset, a background in building complex platform products, and the ability to drive aggressive project timelines while maintaining high engineering standards.
What you will do
- Lead the technical architecture and implementation of key product features for the LangSmith platform.
- Write clean, maintainable, and well-tested code across a technology stack that includes Go, Python, and TypeScript.
- Collaborate closely with product and design teams to iterate on new features.
- Drive aggressive project timelines while ensuring high engineering standards are consistently met.
- Engage directly with top-tier customers and various internal stakeholders as a strong communicator.
What you need
- Bring five or more years of professional software engineering experience working on complex platform products.
- Demonstrate fullstack engineering capabilities with backend languages like Go or Python alongside React and TypeScript on the frontend.
- Possess a strong understanding of database systems, particularly Postgres and Redis.
- Show proven experience designing and scaling APIs within high-performance, data-intensive applications.
- Exhibit a hands-on attitude focused on shipping fast and iterating based on direct user feedback.
Nice to have
- Experience with AI and LLM-powered applications
- Experience with developer tools
- Experience with observability platforms
Benefits
- Medical coverage
- Dental coverage
- Vision coverage
- Flexible vacation
- 401(k) plan
- Meals on in-office days in the US
Skills and tech stack
Questions candidates ask
What is the location policy for this position?
This role is onsite 5 days/week in Boston, MA.
What is the salary range for the role?
The annual salary range is $175,000-$240,000 USD.
What does the compensation package include beyond base salary?
The compensation package includes variable compensation for relevant roles, meaningful equity, benefits, and perks.