Fullstack Software Engineer, Agent Platform

About the role

The Agent Platform is the central system Mercor uses to build, run, and showcase AI agents. It functions as both the internal workbench for our teams and the live storefront demonstrated to enterprise clients. As a Full Stack Software Engineer on the Agent Platform team, you will own the complete lifecycle of features across this platform, from initial discovery and technical design through implementation, testing, and production deployment. This role requires you to deeply understand user needs and translate them into robust, scalable software that feels effortless to use. You will be responsible for both the client-facing React interfaces and the server-side services that power agent orchestration and data flow. The work you do will directly support hundreds of internal power users and dozens of enterprise customers running critical workflows. You will build systems that are not only technically sound but also polished and demo-ready at all times. Collaboration with researchers, operators, and AI companies will ensure your work stays aligned with real-world needs. Ultimately, your contributions will define the reliability and capabilities of Mercor's core product offering.

This role is based in our San Francisco office, with engagement requiring full-time in-person work five days per week.

What you'll do

• Design, build, and maintain the full stack of the Mercor agent platform, including React frontends, backend APIs, and data pipelines.
• Enable hundreds of internal users and dozens of enterprise clients by delivering reliable features with production-grade polish and performance.
• Architect and implement foundational infrastructure that allows other teams to rapidly build new agent use cases and task formats.
• Own the end-to-end delivery of high-leverage product features that improve both internal efficiency and customer experience.
• Collaborate closely with Applied AI researchers, product managers, designers, and operations to turn ambiguous requirements into clear technical solutions.
• Write clean, maintainable code that adheres to best practices in frontend and backend architecture for long-term scalability.
• Diagnose and resolve complex issues in high-throughput, multi-tenant environments involving large data volumes and real-time workflows.
• Advocate for usability and developer experience, ensuring the platform is intuitive and efficient for all stakeholders.
• Participate in on-call responsibilities to support production services and ensure high availability.
• Contribute to technical documentation and code reviews to maintain high standards across the engineering organization.
• Partner with cross-functional teams to define and iterate on the platform roadmap based on feedback and business priorities.
• Ensure all deliverables are demo-ready and meet the rigorous standards expected by internal users and enterprise clients.

Requirements

• 2+ years of fullstack engineering experience building and shipping production software.
• Deep proficiency in JavaScript/TypeScript with a strong focus on React and Next.js frontend architectures.
• Solid backend experience in Python and/or Node.js, including relational database design and REST API development.
• Strong understanding of frontend state management patterns and design systems.
• Experience designing systems that handle complex, high-throughput data pipelines and multi-tenant architectures.
• High ownership mindset with the ability to navigate ambiguity and drive projects from conception to delivery.
• Excellent communication skills for articulating technical tradeoffs and collaborating with diverse stakeholders.

Nice to have

• Experience building agent frameworks, LLM-powered products, or human-in-the-loop AI workflows.
• Background in design systems, developer-facing APIs, or internal platform engineering.
• Exposure to AI tools, real-time data, or data visualization technologies.
• Experience working at top-tier technology companies or fast-scaling startups.

Why this role matters

The platform you build is Mercor's core agent product - run internally and shown to every enterprise client. The systems you ship will be used daily by hundreds of internal users and dozens of enterprise clients. You'll help define how new agent use cases are built, delivered, and demonstrated at Mercor. Your work directly shapes both how Mercor works and how customers experience us.

Benefits

• Bi-annual performance bonus structure
• Generous equity grant vested over 4 years
• Up to $15k Relocation bonus
• $10K proximity bonus (if you live within 0.5 miles of our office)
• $1.5K monthly stipend for meals
• Free Equinox membership
• $200 monthly laundry reimbursement
• $200 monthly personal wellness reimbursement
• Health, Dental, Vision insurance