Principal Software Engineer - Networking

What You'll Do

As a Principal Software Engineer - Networking, you will help set the technical direction for Radiant's networking software, and lead the design and delivery of the systems that build, automate, and operate the fabric connecting our GPU clusters.

You'll work across high-performance cluster fabrics, network automation, Managed Networks, and multi-tenant isolation. You'll partner closely with product, infrastructure, SRE, storage, and security teams, and with customers whose workloads depend on the network.

This is a hands-on technical leadership role focused on making our networks fast, reliable, and fully software-driven, through architecture, code, and the standards other teams build on.

Key Responsibilities

• Set the technical vision and architecture for Radiant's networking software, and lead its design and implementation.

• Design and build the control plane that provisions, configures, and automates our cluster fabrics and Managed Networks.

• Translate product and customer requirements into robust architectures, APIs, and technical designs, working closely with Product.

• Own network performance, isolation, and reliability for AI training and inference workloads.

• Lead integration of networking with compute, Kubernetes, storage, security, and observability.

• Drive operational excellence with SRE and Infra Ops, including automation, monitoring, and incident response.

• Raise the engineering bar across the organisation through mentoring, design and code review, and technical standards.

Your Profile

• Extensive experience building and operating large-scale network software or software-driven networks.

• A track record of technical leadership at staff or principal level, including setting direction across multiple teams and delivering complex, high-stakes systems.

• Strong hands-on engineering skills in one or more systems languages such as Go or similar.

• Deep technical expertise across:

• Fabrics: RDMA, InfiniBand, RoCE, Ethernet at scale, congestion control

• Networking: routing, switching, BGP, EVPN/VXLAN, overlays an