Lead HPC Network Architect for AI Compute

Fuse Energy; Greater London; On-site; GBP 90,000 - 150,000; Full time

Benefits offered by this job

Equity opportunity

Fully expensed tech

Private health insurance

Breakfast and dinner allowance

Job summary

Fuse Energy, an AI-first energy company, is hiring a senior network engineer to design, deploy and operate our lossless, RDMA-capable fabrics across GPU compute and storage traffic. You will manage leaf-spine data centre fabrics, enforce tenant isolation, and automate provisioning with Ansible and Python.

You’ll build telemetry, troubleshoot end-to-end performance, and own the office network, while mentoring teammates.

Qualifications

• 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, understanding why lossless behaviour matters for GPU workloads
• Network automation as a working practice: 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
• Clear communicator who enjoys teaching

Responsibilities

• Design and operate lossless, RDMA-capable fabrics for GPU compute and storage traffic.
• 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 catch congestion and link degradation before tenants do
• 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 office-to-data-centre connectivity
• Upskill colleagues on networking through documentation, run-throughs and pairing

Skills

Network engineering

BGP & EVPN/VXLAN

Leaf-spine/Clos fabrics

Linux networking stack

RDMA fabrics (RoCEv2/InfiniBand)

Network automation (Python/Ansible)

Telemetry/Monitoring (Prometheus/Grafa

Wired/wireless campus networks

Clear communication/teaching

Tools

Ansible

Python

NetBox

Prometheus

Grafana

NVIDIA Spectrum-X

Quantum InfiniBand

ConnectX/BlueField NICs

MAAS

PXE

Redfish

Job description

Fuse Energy, an AI-first energy company, is hiring a senior network engineer to design, deploy and operate our lossless, RDMA-capable fabrics across GPU compute and storage traffic. You will manage leaf-spine data centre fabrics, enforce tenant isolation, and automate provisioning with Ansible and Python.

You’ll build telemetry, troubleshoot end-to-end performance, and own the office network, while mentoring teammates.