Senior Software Engineer – AI Middleware

Overview

At Cornelis we’re building the future of AI and HPC networking with an AI-first approach to silicon and software development. We’re seeking engineers who are energized by working on cutting-edge ASIC design and distributed software systems, and who are motivated to push the boundaries on how AI can transform everything from chip architecture to system performance nelis Networks delivers the world’s highest performance scale-out networking solutions for AI and HPC datacenters.

Our differentiated architecture seamlessly integrates hardware, software and system level technologies to maximize the efficiency of GPU, CPU and accelerator-based compute clusters at any scale. Our solutions drive breakthroughs in AI & HPC workloads, empowering our customers to push the boundaries of innovation. Backed by top-tier venture capital and strategic investors, we are committed to innovation, performance and scalability - solving the world’s most demanding computational challenges with our next-generation networking solutions.

We are a fast-growing, forward-thinking team of architects, engineers, and business professionals with a proven track record of building successful products and companies. As a global organization, our team spans multiple U.S. states and six countries, and we continue to expand with exceptional talent in onsite, hybrid, and fully remote roles.

• Design and implement performance-critical features for CCL enablement on Cornelis Networks’ fabrics.
• Optimize distributed training performance across multi-node, multi-GPU configurations.
• Improve GPU communication paths including GPU-direct transfers, IPC, and CPU/GPU synchronization.
• Profile distributed AI workloads and identify bottlenecks across the software and hardware stack.
• Tune AI frameworks such as PyTorch Distributed, Tensor Flow/XLA, JAX, Deep Speed, and Megatron-LM.
• Develop benchmarks and microbenchmarks aligned with real model performance.
• Contribute upstream to AI communication and distributed training projects.
• Participate in design reviews, code reviews, CI, and long-term maintenance.
• Prototype and validate Ultra Ethernet capabilities for AI collective communication.
• Provide technical input for deployment considerations and performance validation.
• Collaborate with kernel/driver, switch, performance, and systems teams.
• Support advanced escalations by analyzing traces and providing robust fixes.

• 8+ years of experience in high-performance systems programming in C/C++ on Linux.
• Strong experience with GPU communication stacks including CUDA/ROCm and NCCL/RCCL.
• Ability to optimize distributed training performance using profiling and tracing.
• Understanding of collective communication concepts and topology awareness.
• Experience delivering production-quality code.
• Open-source contributions in relevant areas.

• Experience with AI frameworks such as PyTorch Distributed, Deep Speed, and Megatron-LM.
• Familiarity with libfabric/OFI, UCX, and RDMA concepts.
• Experience with RoCEv2 and Ultra Ethernet.
• Experience building cluster-scale performance test infrastructure.

This is a remote position for employees residing within the United States.

We offer a competitive compensation package that includes equity, cash, and incentives, along with health and retirement benefits. Our dynamic, flexible work environment provides the opportunity to collaborate with some of the most influential names in the semiconductor industry.

At Cornelis Networks your base salary is only one component of your comprehensive total rewards package. Your base pay will be determined by factors such as your skills, qualifications, experience, and location relative to the hiring range for…