Software Engineer, Agentic Product

Mercor is defining the future of work. We partner with leading AI labs and enterprises to provide the human intelligence essential to AI development.

Our vast talent network trains frontier AI models in the same way teachers teach students: by sharing knowledge, experience, and context that can't be captured in code alone. Today, more than 30,000 experts in our network collectively earn over $2 million a day.

Mercor is creating a new category of work where expertise powers AI advancement. Achieving this requires an ambitious, fast-paced and deeply committed team. You’ll work alongside researchers, operators, and AI companies at the forefront of shaping the systems that are redefining society.

Mercor is a profitable Series C company valued at $10 billion. We work in-person five days a week in our San Francisco, NYC, or London offices.

About the Role

We're looking for a full-stack engineer with strong technical fundamentals and exceptional product taste. The role is ideal for someone who enjoys owning features end-to-end, building at the frontier of research and engineering, and making high-impact contributions to the business.

You will own the entire feature development lifecycle and spend roughly 70% of your time on the backend and 30% of your time on the frontend.

You will work on things like: expanding the capabilities of RL environments, building agentic harnesses, deploying agents to real users and iterating on feedback, designing product features for evaluating models and analyzing their failures, creating synthetic data platforms.

You will move fast, ship often, talk to researchers or power users of AI agents, and solve ambiguous problems that no one has solved before.

Our Tech Stack

Backend: LangSmith, Harbor, Python, FastAPI/Django, PlanetScale

Frontend: TypeScript, React, DuckDB

Infra: AWS, Modal, Kubernetes

What You’ll Do

• Own product features end-to-end, from scoping and design to implementation, launch, and iteration

• Develop intuition for how models and agents hill-climb

• Build and maintain backend services in Python & frontend experiences in Typescript

• Build at the frontier of agentic harnesses and research ideas

• Be obsessed about product quality and service reliability

• Partner closely with Product and Design to make trade-offs between speed, quality, and long-term maintainability

• Raise the bar for code quality, system design, and product craftsmanship through reviews and collaboration

What We’re Looking For:

• Technical

  • Strong proficiency in Python, TypeScript/React, and relational databases.

  • Experience working with LLM & agent frameworks.

  • Solid CS fundamentals around system design, data structures, and distributed systems.

• Execution & Ownership

  • Bias toward action and ownership. You take responsibility for outcomes, not just tasks

  • Ability to balance speed with long-term quality and know when "good enough" is correct

  • Clear communicator who can align technical decisions with business goals

• Product & Taste

  • You obsess over the details & love talking to your users

  • You use the product that you build and keep iterating until it’s done

  • You have strong product opinions and can articulate your design decisions

• Nice to Have

  • Prior experience in a high-growth startup or 0-to-1 product environment

Why Mercor

• Impact: Your work directly powers the world’s leading AI models.

• Learning: Build at the frontier

• Growth: You will have high ownership over your work. You can shape the direction of the product and the company.

Benefits

• Generous equity grant vested over 4 years

• A $1.5K monthly stipend for meals

• Lifestyle & wellness monthly stipend

• Free Equinox membership

• Health insurance

• A $10K housing bonus (if you live within 0.5 miles of our office)