Software Engineer, Distributed Training

We are looking for exceptional systems engineers to build the distributed training engines behind the River API. Your goal is to make fine-tuning and reinforcement learning fast, numerically correct, and reliable across large GPU clusters.

You will own the execution of training workloads, including gradient computation, optimizer updates, rollout coordination, and checkpoint recovery. Working closely with researchers and inference engineers, you will bring new learning methods into production and improve how efficiently models use compute.