Senior Back-End Network Engineer - AI Infrastructure Operations

Within Nscale, the Network Operations team is responsible for the performance and reliability of the high-speed interconnect fabrics that underpin our AI and HPC platforms. These networks are critical to distributed training and inference workloads and demand a deep operational focus., In this role, you will be responsible for the day-to-day health, stability, and performance of Nscale's large-scale Infiniband and RDMA over Converged Ethernet (RoCE) fabrics. You'll bring deep operational expertise from high-performance or hyperscale environments and play a key role in incident response, performance tuning, and continuous improvement of latency-sensitive AI networking systems.

What You'll be Doing Owning the operational health, configuration consistency, and performance tuning of large-scale Infiniband and RoCE fabrics supporting AI and HPC workloads Leading the diagnosis and resolution of complex network incidents (P0/P1), spanning firmware, kernel drivers, switch hardware, and application or middleware layers Driving blameless postmortems and implementing preventative fixes to improve long-term fabric stability and availability Partnering with SREs to define requirements for automation and tooling, and contributing where appropriate to network provisioning, validation, and monitoring systems Collaborating with Network Architecture and Engineering teams to validate fabric designs and enforce standards for routing, congestion control, and firmware baselines Monitoring fabric utilisation and performance, identifying bottlenecks, and tuning for congestion, microbursts, and predictable latency Acting as a subject matter expert for cross-functional teams on high-speed networking, RDMA behaviour, and fabric-level performance characteristics

• Participating in an on-call rotation supporting mission-critical, customer-facing infrastructure

Do you have experience in Tooling?, 5+ years of experience in network engineering, with at least 3 years operating HPC or large-scale AI interconnect networks Deep, hands-on operational experience with Infiniband and/or modern RoCE deployments Expert understanding of RDMA concepts, protocols, and troubleshooting techniques Strong fundamentals in data centre networking, including TCP/IP, BGP, OSPF, and leaf-spine architectures Proven ability to troubleshoot complex network issues using Linux-based tooling and fabric diagnostics Proficiency in Python, Go, or shell scripting for automation, data analysis, or configuration management

• Experience working in a 24/7 operational environment with a strong focus on reliability and toil reduction

Nice to Have Experience operating NVIDIA/Mellanox Spectrum switches and ConnectX NICs at scale Familiarity with AI or ML training workflows and the impact of network performance on distributed frameworks Experience with network observability and telemetry systems such as streaming telemetry, sFlow, Prometheus, or Grafana

• Knowledge of GPU communication libraries such as NVIDIA NCCL

• 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.

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.