Research Engineer, RL Environments and Infrastructure

That British Chick is partnering with a confidential early-stage AI company building data, evaluation, and infrastructure systems for frontier AI models and deployed agents. The company is seeking a Research Engineer to build reinforcement-learning environments, evaluation systems, reward mechanisms, and production infrastructure that assess training value and model performance.

Responsibilities:

• Build systems that rank tasks and datasets by expected training value before significant compute is spent
• Design automated scoring and evaluation infrastructure that can run continuously and economically at scale
• Develop evaluations around real-world customer outcomes rather than generic correctness benchmarks
• Identify drift between production traffic and existing evaluation sets and rebuild evaluations when necessary
• Design reward mechanisms, graders, and checkers that remain reliable as models learn to exploit weaknesses
• Own ambiguous evaluation problems end-to-end, from initial research and prototyping through production implementation and iteration
• Work closely with researchers and engineers across training, data, and infrastructure