Senior Software Developer - Network and Collectives

About the team:
Network and Collectives owns the scale-out communication substrate for our AI accelerator - the NCCL equivalent for our hardware. We turn many chips into one machine: all-reduce, all-gather, reduce-scatter and point-to-point, made topology-aware and mapped onto the rack/pod interconnect.

We are measured on real fabric across a pod, not on a single card, and we pair tightly with the Tray/Rack/Pod/Cluster HW pillar and the Multi-Node Runtime team.

What you will do:

• Design and implement collective algorithms tuned to our interconnect topology and bandwidth/latency profile.
• Build a topology-aware transport layer over the tray/rack/pod.
• Optimize end-to-end collective performance across multi-node pods; profile, find bottlenecks, and close the gap to fabric peak.
• Co-design with HW on interconnect features, and with Multi-Node Runtime on partitioning, overlap, and scheduling.
• Own correctness and numerical determinism of reductions across scale-out.

• 5+ years AI/Systems/HPC software in C++; strong concurrency and lock-free design.
• Hands-on with collective libraries (NCCL/MPI/etc) or scale-out communication.
• Working knowledge of the communication patterns behind tensor, pipeline, and expert parallelism, and how they map onto collectives and the underlying fabric.
• Performance engineering: profiling, bandwidth/latency tuning, roofline reasoning.

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