GPU Cluster Engineer

Sciforium is an AI infrastructure company developing next-generation multimodal AI models and a proprietary, high-efficiency serving platform. Backed by multi-million-dollar funding and direct sponsorship from AMD with hands-on support from AMD engineers the team is scaling rapidly to build the full stack powering frontier AI models and real-time applications.

Role Overview

We are looking for a Senior Network Engineer to own the complete networking stack of our GPU clusters — from the RDMA compute fabric to the data center perimeter to cross-site and cloud connectivity. You will design the network architecture for new large-scale clusters, lead its bring-up, and operate it in production. This role owns everything from the NIC port outward: backend InfiniBand/RoCE fabrics, frontend and storage networks, out-of-band management, firewalls and edge security, and the links that connect our clusters to each other and to the cloud. You will work alongside our Hardware Operations team (physical install) and Systems & Platform team (host software stack) to deliver a fabric that never becomes the bottleneck.

Key Responsibilities

• Fabric Architecture & Cluster Network Design

  • Greenfield Design: Architect the full network for new GPU clusters — compute/backend fabric, storage network, in-band frontend, out-of-band management (BMC/IPMI), and perimeter — including topology (fat-tree/Clos, rail-optimized), oversubscription analysis, and growth planning.

  • RDMA Fabric Selection: Design and justify InfiniBand (NDR/XDR, Quantum-class) vs. lossless Ethernet/RoCE v2 (Spectrum-X, Tomahawk-class) fabrics for training and inference workloads, including scale-up domains (NVLink/NVSwitch, NVL72-class rack systems).

  • Hardware & Physical Plant: Specify switches, NICs (ConnectX/BlueField), optics (400/800G OSFP/QSFP-DD), and cabling plans; produce the port maps and cable schedules Hardware Operations executes.

  • Logical Design: Own IP addressing plans, VLAN/VRF segmentation, and BGP/EVPN-VXLAN underlay-overlay architecture.

• RDMA & Performance Engineering

  • Lossless Ethernet: Configure and validate RoCE v2 at scale — PFC, ECN/DCQCN congestion control, QoS/DSCP classification, buffer tuning — and prove no-drop behavior under full training load.

  • InfiniBand Operations: Run subnet managers (UFM/OpenSM), adaptive routing, SHARP in-network aggregation, partition keys, and virtual-lane QoS.

  • Fabric Validation: Benchmark and sign off new fabrics with perftest/ib_write_bw and nccl-tests/rccl-tests; verify GPUDirect RDMA paths and topology-aware placement with the Systems & Platform team.