Software Engineer, River API

River AI is building personal AI systems across hardware, training infrastructure, user interfaces, and deep learning research. The Software Engineer will develop and own high-performance infrastructure for model training and inference, including distributed systems, GPU kernels, system profiling, and collaboration with research scientists.

Responsibilities:

• Architect and deploy fault-tolerant distributed systems for training and inference workloads across clusters with thousands of nodes
• Design high-performance kernels to maximize tensor operation efficiency, memory throughput, and networking over InfiniBand/RDMA
• Profile systems end-to-end to resolve blockers across hardware, software, data loading pipelines, and collective communication primitives
• Partner directly with research scientists to rapidly implement, optimize, and scale experimental model architectures