Full-Stack Software Engineer, Design

ABOUT THE ROLE Join a growing team building AI infrastructure for creating and evaluating reinforcement learning environments. You will design and build product interfaces that help users understand agent behavior, interpret evaluation results, and improve training workflows. WHAT YOU'LL DO - Design and build interfaces across the platform and marketplace, from early concepts through launch. - Make agent runs, evaluation results, reward signals, and quality feedback clear and actionable. - Work with research and engineering to turn complex reinforcement learning and evaluation workflows into useful tools. - Speak with users, observe where they struggle, and improve the product based on feedback. - Develop thoughtful interaction patterns while maintaining a high bar for usability, visual quality, and implementation. WHAT WE'RE LOOKING FOR - At least 3 years in a design engineering, product design, or similar role shipping product interfaces. - Experience working primarily as a full-stack engineer while also designing interfaces, and a portfolio showing shipped design-engineering work. - Front-end engineering skills and experience turning designs into working product interfaces. - A technical education or equivalent technical background, with the ability to understand complex concepts and communicate them clearly. - A track record of shipping products, learning from users, and improving what you build. - Experience collaborating closely with engineers and researchers. - Developer tools, data-rich products, research software, reusable interface patterns, or early-stage company experience are useful. Familiarity with AI agents, evaluations, reinforcement learning, or training data is also helpful. COMPENSATION & BENEFITS Base salary: $130,000 to $225,000 USD annually. Visa sponsorship is available. LOCATION On-site in San Francisco, California, with remote work options available.