Software Engineer, Full-Stack (Agent Harness & Interfaces)

We are seeking a Full-Stack Software Engineer to build the interactive layer between our advanced reasoning agents and the human world.

While our core models and backend sandboxes execute complex logic, you will build the “Harness”—the platforms, developer consoles, and user interfaces that make these capabilities accessible, observable, and steerable. You will craft the developer experience for our model tuning platforms and build the rich, real-time interfaces where users collaborate with autonomous AI Scientists.

In this role, you sit at the intersection of product design, API architecture, and frontend engineering, transforming raw computational power into a magical user experience.

Agent Interaction & Observability: Build rich, real-time web interfaces to visualize long horizon agent trajectories.

Developer Console & PaaS UI: Architect and develop the front-end and middle-tier APIs for our model tuning and deployment platform. You will build intuitive workflows for users to upload data, trigger fine-tuning jobs, and manage cloud/edge compute nodes.

Real-Time Streaming Systems: Implement robust, low-latency communication layers to stream complex model outputs, code execution results, and telemetry data from the backend sandboxes to the client.

UX/UI Prototyping: Collaborate closely with Product Managers and Designers to iterate rapidly on user experiences, ensuring our tools feel incredibly responsive, modern, and powerful (akin to top-tier developer tools).

Engineering Standardization & Delivery: Establish engineering standards and drive standardized delivery across the stack, including code quality, testing, release processes, documentation, observability, and maintainable production operations.

3+ years of experience in full-stack web development with a strong emphasis on modern frontend ecosystems.

Frontend & Backend Full Stack Mastery: Deep expertise in React, Next.js, TypeScript, and state management for complex web applications. Strong proficiency in Python or Node.js to build middle-tier services that interface with our core ML infrastructure.

System Design: Experience designing RESTful and real-time APIs, with a solid understanding of database design.

Engineering Delivery: Experience driving standardized engineering delivery, including scalable codebase conventions, testing practices, CI/CD workflows, documentation, and cross-functional execution for production systems.

Experience building developer tools, ML observability dashboards, or AI-native applications (e.g., using Vercel AI SDK, LangChain).

A strong portfolio demonstrating high-quality UI/UX design sensibilities and polished interactive web experiences.

Familiarity with WebGL/Canvas for data visualization or rendering complex system architectures.

Experience in improving engineering productivity and software quality through reusable frameworks, platform standards, and releasing best practices.