Senior Network Engineer

About the role

As a Senior Network Engineer you will design, deploy, and operate the high‑performance, low‑latency network fabric that underpins Radiant’s GPU infrastructure. You will shape the architecture, automation and operational standards of the network to meet the rigorous demands of modern AI training and inference workloads.

Key responsibilities

• Design scalable leaf‑spine networks using Mellanox switches with Cumulus Linux, integrated with Juniper PTX routers and SRX firewalls.
• Lead collaboration with third‑party and internal providers to deploy resilient site‑to‑site and internet connectivity, optimise topology and resolve complex faults.
• Perform configuration, upgrades and deep troubleshooting of Juniper and NVIDIA/Cumulus devices in production.
• Implement programmable network designs using controller‑based SDN platforms.
• Support Kubernetes networking with CNIs such as Calico, Cilium or Kube‑OVN and understand micro‑services traffic patterns.
• Develop and maintain Ansible playbooks and Python automation for configuration management, provisioning and compliance.
• Implement observability tools using SNMP, sFlow and gRPC to detect network bottlenecks at scale.
• Lead L3/L4 incident response, escalation management and root‑cause analysis in 24×7 environments.
• Engage with internal stakeholders and enterprise customers as a trusted technical expert.

Required profile

• 3–5 years experience supporting high‑throughput, low‑latency infrastructure for GPU‑based or HPC clusters.
• 8–12+ years in networking, including at least 5 years in globally distributed environments.
• Hands‑on experience with multi‑region/backbone networks, high‑availability design and large‑scale routing (BGP/MPLS).
• Strong understanding of BGP, EVPN, VXLAN and Data Centre Interconnects.
• Proficiency with Linux CLI, scripting and diagnostics.
• Experience delivering L3/L4 production support and driving root‑cause remediation.

Required skills

• Mellanox Ethernet switches
• Cumulus Linux
• Juniper PTX routers
• Juniper SRX firewalls
• BGP, EVPN, VXLAN
• Data Centre Interconnects (DCI)
• Kubernetes networking
• Calico, Cilium, Kube‑OVN CNIs
• Ansible
• Python
• Terraform (optional)
• SNMP, sFlow, gRPC

What we offer

• 25 days of annual leave and enhanced parental pay & leave.
• Private medical insurance via Bupa.
• Cycle‑to‑Work scheme and Gympass subscription.
• Company shares program and dedicated learning time.
• Inclusive culture that values diversity, open communication and results‑focused work.