About this role
Salary: £63,000 - 103,000 per year
Requirements: 5+ years as a network engineer operating production data centre networksStrong dynamic routing experience, particularly BGP, plus overlay/encapsulation design and troubleshooting such as EVPN/VXLANHands-on experience with leaf-spine / Clos fabric design and operationExperience with modern data centre network operating systems and comfort with the Linux networking stack, not just a vendor CLIPractical RDMA fabric experience, such as lossless Ethernet with RoCEv2 and PFC/ECN/DCQCN tuning, or InfiniBand, with an understanding of why lossless behaviour matters for GPU workloadsNetwork automation as a working practice, including scripting such as Python, configuration management such as Ansible, config generation from a source of truth, and version-controlled changesSolid Linux administration fundamentals, with the ability to debug from the host side as well as the switch sideExperience with network telemetry and monitoring, such as Prometheus/Grafana, sFlow/IPFIX, or streaming telemetryExperience running corporate/campus networks, including wired and wireless, switching, NAC/802.1X, VPN, and remote accessClear communicator who enjoys teaching and can document, pair, and run sessions that bring less network-savvy colleagues up to speedRelevant certifications such as CCNP/CCIE or equivalent are valued as evidence of depth, not a gate Responsibilities: Design and operate lossless, RDMA-capable fabrics for GPU compute and storage traffic, including QoS, congestion control, and buffer tuning at scaleBuild and manage leaf-spine data centre fabrics, with routed underlay and overlay designImplement and maintain per-tenant network isolation across compute, storage, and management planesAutomate network provisioning, configuration, and validation, treating switch config as code and deploying through CIBuild telemetry and observability for the fabric, including dashboards and alerting that catches congestion and link degradation earlyTroubleshoot performance issues end to end, from optics and cabling through switch buffers to NIC/DPU configuration and collective-communication behaviour on the hostsOperate the out-of-band management network, console access, and remote recovery pathsSupport tenant onboarding, including segmentation and addressing, bandwidth and isolation guarantees, and capacity planning as the cluster scalesWrite clear design documentation capturing decisions, rationale, and rejected alternativesOwn and maintain the office network, including wired and wireless infrastructure, firewalling, VPN/remote access, and connectivity between the office and data centre environmentsUpskill colleagues on networking through documentation, run-throughs, and pairing so the wider team can operate and troubleshoot the fabric confidently Technologies: AIAnsibleEthernetFabricGrafanaInfiniBandSupportLESSLinuxNetworkPrometheusPythonRDMAVPNBootstrapCiscoDatadogFirewallFortiGateFlowNodeJS More:
We are Fuse Energy, a forward-thinking renewable energy startup on a mission to deliver a terawatt of renewable energy fast. We combine first-principles thinking with cutting-edge technology to build a radically better energy system. We have raised $210M from top-tier investors including Multicoin, Balderton, Lakestar, Accel, Creandum, Lowercarbon, Ribbit, Box Group, and strategic angels such as Nico Rosberg, the Co-Founder of Solana, and GPs behind Meta, Revolut, Spotify, Uber, and more. This is a full-time role focused on designing, deploying, and operating the network fabric for our multi-tenant AI cluster, plus owning the office network and acting as the networking authority for the company. We offer a competitive salary, an equity sign-on bonus, a biannual bonus scheme, fully expensed tech to match your needs, and breakfast and dinner allowance for office-based employees.
last updated 36 week of 2026