Senior Network Engineer – Deployment

Nscale; Greater London; On-site; GBP 70,000 - 110,000; Full time

Job summary

Nscale is seeking a Senior Network Engineer to build and bring up the networks behind GPU clusters across Europe. The role is hands-on, taking network designs from hardware arrival on site through to customer acceptance.

You'll deploy, validate, and troubleshoot high-performance fabrics (Ethernet/InfiniBand), develop automation, and document runbooks to ensure repeatable builds across sites. This role involves regular travel across Europe and collaboration with PMs and vendors.

Qualifications

• 5+ years of network engineering experience in large-scale data centre, cloud, or HPC environments.
• Experience at a hyperscaler or major network vendor or a comparable large-scale network.
• Strong hands-on knowledge of routing and switching: BGP, OSPF, EVPN/VXLAN, ECMP, and L2/L3 data centre design.
• Experience deploying and operating cluster networks, ideally including InfiniBand or RoCE fabrics.
• Practical experience with network automation (Python, Ansible, or similar).
• Willingness to travel across Europe to sites as needed.

Responsibilities

• Deploy, configure, and validate high-performance Ethernet and InfiniBand fabrics for large GPU clusters.
• Bring up front-end, storage, and management networks and WAN edge connectivity for new sites and expansions.
• Run network acceptance testing and performance validation ahead of customer handover.
• Troubleshoot and resolve issues across routing, switching, optics, and cabling during build and early life.
• Work with Network Architecture to refine reference designs, BOMs, and build standards based on what you learn in the field.
• Build and improve automation for provisioning, configuration, and validation.
• Partner with Technical Program Managers, Data Centre Operations, and vendors to keep builds on schedule.
• Write clear runbooks and documentation so builds are repeatable across sites.

Skills

Network engineering

Routing & Switching

Network automation

Travel readiness

Cloud / Data centre

Tools

InfiniBand

RoCE

Python

Ansible

Job description

About Nscale

Nscale is the GPU cloud engineered for AI. We provide cost-effective, high-performance infrastructure for AI start-ups and large enterprise customers. Nscale enables AI-focused companies to achieve superior results by reducing the complexity of AI development. Our GPU cloud bolsters technical capabilities and directly supports strategic business outcomes, including cost management, rapid innovation, and environmental responsibility.

We thrive on a culture of relentless innovation, ownership, and accountability, where every team member takes pride in their work and drives it with excellence and urgency. As an Nscaler, you'll build trust through openness and transparency, where everyone is inspired to do their best work. If you join our team, you'll be contributing to building the technology that powers the future.

About the Role

We're looking for a Senior Network Engineer to build and bring up the networks behind Nscale's GPU clusters across Europe. You'll join our Deployment organisation, a build org that owns every step from hardware arrival on site through to customer acceptance.

This is a hands-on engineering role. You'll take network designs into production: configuring and validating cluster fabrics, front-end networks, and WAN edge, troubleshooting issues during bring-up, and making sure every build is ready for customers. The role involves regular travel to our sites.

What You'll be Doing

• Deploy, configure, and validate high-performance Ethernet and InfiniBand fabrics for large GPU clusters.
• Bring up front-end, storage, and management networks and WAN edge connectivity for new sites and expansions.
• Run network acceptance testing and performance validation ahead of customer handover.
• Troubleshoot and resolve issues across routing, switching, optics, and cabling during build and early life.
• Work with Network Architecture to refine reference designs, BOMs, and build standards based on what you learn in the field.
• Build and improve automation for provisioning, configuration, and validation.
• Partner with Technical Program Managers, Data Centre Operations, and vendors to keep builds on schedule.
• Write clear runbooks and documentation so builds are repeatable across sites.

About You

• 5+ years of network engineering experience in large-scale data centre, cloud, or HPC environments.
• Experience at a hyperscaler or major network vendor (e.g. Microsoft, AWS, Oracle/OCI, Cisco) or a comparable large-scale network.
• Strong hands-on knowledge of routing and switching: BGP, OSPF, EVPN/VXLAN, ECMP, and L2/L3 data centre design.
• Experience deploying and operating cluster networks, ideally including InfiniBand or RoCE fabrics.
• Practical experience with network automation (Python, Ansible, or similar).
• Calm, methodical troubleshooter who can work under deadline pressure on live builds.
• Willingness to travel across Europe to sites as needed.

Nice to Have

• Experience building networks for GPU clusters or AI training environments.
• Familiarity with HPC topologies (Fat Tree, Rail) and 400G/800G optics.
• Experience with SONiC, Cumulus, or other open networking platforms.
• WAN, peering, or DWDM experience.
• Industry certifications such as CCNP/CCIE, JNCIP/JNCIE, or NVIDIA networking certifications.

Why this role matters

The network is what turns thousands of GPUs into a single system. Your work decides how fast new clusters reach customers and how well they perform once they do.

Equal Opportunities Statement

At Nscale, we are committed to fostering an inclusive, diverse, and equitable workplace. We believe that a variety of perspectives enriches our work environment, and we encourage applications from candidates of all backgrounds, experiences, and abilities. We strongly encourage applications from people of colour, the LGBTQ+ community, people with disabilities, neurodivergent people, parents, carers, and people from lower socio-economic backgrounds.

If there's anything we can do to accommodate your specific situation, please let us know.

The responsibilities outlined in this job description are not exhaustive and are intended to provide a general overview of the position. The employee may be required to perform additional duties, tasks, and responsibilities as assigned by management, consistent with the skills and qualifications required for the role.

For information on how Nscale handles candidate personal data, please see our Employee & Candidate Privacy Notice: Here. Nscale does not accept unsolicited candidate submissions from recruitment agencies.