Senior Infrastructure Support Engineer Remote, UK in London

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.

At Nscale, our Support and Operations team plays a critical role in maintaining service availability, driving service reliability and rapid response to customer tickets. 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 (Job Purpose)

We're looking for an Engineer that has good people, leadership & technical skills. A technical expert responsible for ensuring the efficiency, reliability, and scalability of data centre infrastructure. You're comfortable problem solving & making decisions on complex topics with high levels of ambiguity in a results driven environment. You're comfortable influencing without authority and exceptional at building relationships with senior stakeholders across the business to get things done. You have the understanding and skillset to grasp technical concepts and problems quickly. You have strong analytical skills. You're a doer who is extremely organised and diligent. You're a self-starter, curious, and quick to learn, knowing what questions to ask to get up to speed quickly.

What You'll be Doing (Responsibilities)

• You'll join the Support duty rotation and, as a Senior, will collaborate with Engineering on incidents and changes.
• Proactively improve dashboards, alerts, and runbooks to prevent repeat incidents.
• Contribute to knowledge sharing across Operations and Engineering, including training content, workshops, and PR reviews. Drive to upskill - better the team and yourself.
• Accurately record, update, manage and resolve tickets using the call tracking system whilst keeping all parties (internal or external) informed of the tickets progression via phone and email.
• Demonstrate a solid understanding of the underlying Platform to our customers and providing assistance in helping them leverage the service and products.
• Respond to incoming monitoring alerts, resolving or escalating as required in accordance with priorities and agreed service levels.
• Take decisive actions, and calculated risks, on technically complex incidents and tasks to ensure business speed and efficiency.
• Lead by earning trust, speaking candidly, and benchmark against the best to identify where we can improve.
• Disagree when appropriate and challenge the status quo. Commit wholly to decisions and plans once in motion. Be a technical expert, and drive the team to make the best decisions.
• Deliver project tasks, improvements, and technical assessments in the right quality in a timely fashion.
• Handle escalated customer support issues, providing solutions aligned with business SLA requirements.
• Design and implement automation scripts and tools to optimize processes.
• Conduct root cause analysis for major incidents and recommend long-term fixes.
• Collaborate with cross-functional teams for service improvements.
• Responding to critical incidents during out of business hours, and be on-call as required.

About You (Skills / Qualifications)

• Ability to adapt to customer-driven demands, such as providing specialist support after core business hours, with availability to travel to Nscale or Customer locations to provide onsite technical expertise and guidance.
• Disciplined, organised and self-motivated. Able to motivate, support and mentor other team members.
• Strong leadership principles, with a bias for taking decisive action, working independently, and driving the team and wider organisation to improve.
• Understanding of how datacenters operate and the core datacentre technologies: Servers, Networks, Storage and Virtualisation, ideally gained through an operational support background.
• Good organisational and time management skills, with strong interpersonal skills, able to deal effectively with people at all levels whilst also having good written and verbal communication skills.
• Linux systems engineering at scale. Strong command over modern Linux distributions, kernel modules, systemd, networking stack, and filesystem tooling. Proven troubleshooting across compute, storage and network layers in production.
• Kubernetes. Operate and troubleshoot K8s clusters, and understand how physical resources are abstracted up the stack to K8s.
• GPU platforms (NVIDIA and AMD). Practical experience with GPU drivers and GPU logs investigation tools, e.g. nvidia-smi. Performance diagnostics using NCCL on large scale clusters.
• Observability and incident response. Build and use alerting stacks and dashboards, interpret metrics and alerts, and drive runbooks to resolution; contribute to SLOs and post-incident reviews.
• Strong Networking fundamentals. Solid grasp of L2/L3, routing, BGP, VLANs, VXLAN, firewalls, load balancing. Understanding of high-performance fabrics (RDMA/NVLink basics) for cluster-to-cluster traffic.
• SRE-style operations. Write and maintain runbooks, automate diagnostics, and reduce human intervention using scripts or small tools.
• Cloud Infrastructure Administration and Troubleshooting. Strong familiarity with using virtualisation technologies, and investigating issues that arise, performing deep dive investigation to perform root cause analysis. Openstack operations experience preferred.

Nice to Have

• Automated Network Configuration. Experience automating network deployment configurations and making safe, repeatable changes in business critical environments.
• Strong GPU HPC concepts, beyond standard troubleshooting. Familiarity and prior experience with RDMA/InfiniBand and performance tuning for distributed workloads. Support scheduling for large multi-GPU jobs, containers via Pyxis/Enroot, and MPI. Diagnose queue, topology, and job failures.
• GitOps tooling and cluster/app automation pipelines. Build and maintain CICD pipelines. Re-architecting old scripts to use Github Actions.

What We Can Offer You

At Nscale, you'll find a collaborative, supportive, and innovative environment where your contributions spark real impact. We're building something extraordinary, and we want you at the core. Highly competitive package (base + equity) with reviews every 12 months. Join the fastest-growing tech startup, your chance to push boundaries, collaborate with brilliant minds, and make your mark on cutting-edge AI. Expect a dynamic progression plan tailored to your ambitions. Grow by trying new things, leading, challenging the status quo, and owning your impact, always with our full support. Human-First Flexibility: We treat you as humans first. Our flexible workplace trusts Nscalers to deliver, giving you the autonomy to shape your day around life's moments. Join our thriving remote-first team. Geography is no barrier to impact or connection. We build seamless virtual collaboration, empowering you, wherever you work. 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.