[Hiring] Senior Software Engineer – AI/HPC Middleware @Cornelis Networks, Inc.

Role Description

We are seeking an experienced Senior Software Engineer to contribute to the design, development, and upstream enablement of Cornelis Networks' AI/HPC communication middleware. This role focuses on enabling and optimizing HPC middleware (MPI/SHMEM) and AI middleware (collective communication libraries / CCL, e.g., NCCL/RCCL and related stacks) over Cornelis Networks' interconnects. You will help drive performance, correctness, and deployability across real customer workloads by collaborating across the stack (drivers/kernel, switches, systems, and application/framework teams) and by contributing upstream to key open-source projects.

Key Responsibilities

• AI/HPC Middleware Enablement & Optimization: Implement and help optimize features for HPC middleware (HPI and SHMEM) and AI middleware (CCL stacks ie: NCCL/RCCL and related collective communication libraries).
• Transport & Integration: Assist in integrating middleware capabilities with underlying transports and provider layers (ie: libfabric / OFI, UCX, verbs-like semantics where applicable).
• Upstream & Open-Source Leadership: Prepare and submit upstream contributions across MPI/SHMEM projects, CCL ecosystems, and related components.
• Cross-Stack Collaboration & Performance Validation: Collaborate with kernel/driver and switch teams to help deliver end-to-end performance aligned to the Cornelis product roadmap.
• Customer & Field Impact: Help analyze performance traces and reproduce customer issues, and assist in translating findings into fixes.

Qualifications

• 6+ years of experience in systems programming in C/C++ on Linux.
• Bachelor's degree in Computer Science, Engineering, or related field (or equivalent experience). Master's or Doctorate a plus.
• Hands-on experience with HPC middleware internals (Open MPI, MPICH, MVAPICH, and/or SHMEM) or optimizing collective communications for AI, including NCCL/RCCL, CUDA/ROCm and/or other CCL stacks.
• Demonstrated ability to deliver low-latency/high-throughput communication paths and to diagnose performance issues using profiling/tracing tools.
• Working knowledge of transport/integration layers such as OFI/libfabric, UCX, verbs-style concepts.
• Solid background in RDMA concepts and performance tuning.
• Experience contributing to open-source projects.

Requirements

• Prior experience developing or maintaining libfabric providers.
• Familiarity with Ultra Ethernet (UEC/UET) specifications.
• Experience with RoCEv2, congestion control, and/or Ethernet-based RDMA deployments.
• Experience with cluster-scale benchmarking, profiling, and optimization.
• Background with HPC fabrics, such as Omni-Path.

Benefits

• Competitive compensation package that includes equity, cash, and incentives.
• Health and retirement benefits.
• Medical, dental, and vision coverage.
• Disability and life insurance.
• Dependent care flexible spending account.
• Accidental injury insurance and pet insurance.
• Generous paid holidays.
• 401(k) with company match.
• Open Time Off (OTO) for regular full-time exempt employees.
• Other paid time off benefits include sick time, bonding leave, and pregnancy disability leave.