HPC Network Engineer

• Design and operate lossless, RDMA-capable fabrics (e.g. RoCEv2, InfiniBand) for GPU compute and storage traffic, including QoS, congestion control, and buffer tuning at scale
• Build and manage leaf-spine data centre fabrics, with routed underlay and overlay design (e.g. BGP, EVPN/VXLAN)
• Implement and maintain per-tenant network isolation across compute, storage, and management planes.
• Automate network provisioning, configuration, and validation, treating switch config as code (e.g. Ansible, Python, NetBox as source of truth), deployed through CI
• Build telemetry and observability for the fabric: flow-level and buffer-level visibility, dashboards, and alerting that catches congestion and link degradation before tenants do (e.g. Prometheus/Grafana/Datadog, streaming telemetry)
• Troubleshoot performance issues end to end, from optics and cabling through switch buffers to NIC/DPU configuration and collective-communication behaviour on the hosts
• Operate the out-of-band management network, console access, and remote recovery paths
• Support tenant onboarding: segmentation and addressing, bandwidth and isolation guarantees, and capacity planning as the cluster scales
• Write clear design documentation capturing decisions, rationale, and rejected alternatives
• Own and maintain the office network: wired and wireless infrastructure, firewalling, VPN/remote access, and connectivity between the office and data centre environments
• Upskill colleagues on networking: share knowledge through documentation, run-throughs, and pairing so the wider team can operate and troubleshoot the fabric confidently

• 5+ years as a network engineer operating production data centre networks
• Strong dynamic routing experience (BGP in particular), plus overlay/encapsulation design and troubleshooting (e.g. EVPN/VXLAN)
• Hands-on experience with leaf-spine / Clos fabric design and operation
• Experience with modern data centre network operating systems and comfortable in the Linux networking stack, not just a vendor CLI
• Practical RDMA fabric experience: lossless Ethernet (e.g. RoCEv2 with PFC/ECN/DCQCN tuning) or InfiniBand, with an understanding of why lossless behaviour matters for GPU workloads
• Network automation as a working practice, not an aspiration: scripting (e.g. Python), configuration management (e.g. Ansible), config generation from a source of truth, version-controlled changes
• Solid Linux administration fundamentals: you can debug from the host side as well as the switch side
• Experience with network telemetry and monitoring (e.g. Prometheus/Grafana, sFlow/IPFIX, streaming telemetry)
• Experience running corporate/campus networks: wired and wireless, switching, NAC/802.1X, VPN and remote access (e.g. Cisco Catalyst/Meraki or comparable)
• Clear communicator who enjoys teaching: able to document, pair, and run sessions that bring less network-savvy colleagues up to speed

Nice to have

• Experience with GPU cluster networking specifically (e.g. NVIDIA Spectrum-X or Quantum InfiniBand, ConnectX/BlueField NICs and DPUs, UFM, SHARP, or equivalent Broadcom/Arista AI fabric platforms)
• Container networking experience: CNI plugins and BGP integration between clusters and the fabric.
• Understanding of collective-communication libraries and how fabric behaviour shows up as training/inference performance
• Multi-tenant network design: VRF-based isolation, tenant bandwidth guarantees, secure shared infrastructure
• Experience with enterprise firewall platforms (e.g. FortiGate, Palo Alto), including HA deployment and virtualised/segmented instances
• Storage networking experience (e.g. NVMe-oF, lossless storage fabrics, per-tenant storage isolation)
• Bare-metal provisioning environments (e.g. MAAS, PXE, Redfish) and how network bootstrap fits into node lifecycle
• Optical layer knowledge at 200/400/800G: transceivers, MPO cabling, link qualification
• Experience standing up a data centre network from greenfield
• Relevant certifications (e.g. CCNP/CCIE or equivalent), valued as evidence of depth, not a gate

• Competitive salary and an equity sign-on bonus
• Biannual bonus scheme
• Fully expensed tech to match your needs
• Breakfast and dinner allowance for office-based employees