Research Engineer, Reinforcement Learning

Job DescriptionWant to build the large-scale RL environments frontier labs use to train agents that can truly reason and act?This team are creating complex reinforcement learning environments - simulations where advanced agents learn to plan, adapt, and solve multi-step problems that stretch beyond standard benchmarks. The focus isn't on training the models themselves, but on building the worlds that make meaningful learning and evaluation possible - the foundation for more capable, aligned systems.You'll work end-to-end across environment design, reward dynamics, and scalable simulation - developing the feedback loops that define what "good" looks like for intelligent behaviour. It's open-ended, research-driven work where the task definition, data, and reward structure are often the hardest and most important problems to solve.You'll collaborate closely with researchers tackling unsolved challenges in reinforcement learning and agent behaviour, shaping experiments, scaling infrastructure, and refining how agents learn in the loop.It suits someone with strong ML and RL experience, deep intuition for agent dynamics, and the curiosity to explore problems that don't come with clear instructions.On-site in San Francisco. Compensation up to $300 K base (negotiable, depending on experience) plus equity.If you want to help build the environments that teach the next generation of AI systems how to think, act, and adapt - we'd love to hear from you.