Backend Java Developer Jobs in Seattle, WA

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

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.

We're looking for a Senior Network Engineer – AI Infrastructure to join our Network Operations team.

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

About You

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

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.

Equal Opportunities Statement

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.