Principal Platform Engineer

What You'll Do As a Principal Platform Engineer, you will help set the technical direction for the platform one of our engineering teams builds on: the infrastructure, tooling, and automation that let us run GPU clusters, Kubernetes, and our managed services reliably at scale. You'll partner closely with software engineers, SRE, Infra Ops, and the other platform engineers across Radiant. This is a hands-on technical leadership role focused on making the platform reliable, secure, and easy to build on, through architecture, code, and the standards other teams build on. The teams Infra: the platform behind provisioning and cluster management Network: the platform behind our fabrics and Managed Networks Cloud: the platform behind our Virtual Machines and console Observability: the platform behind FlightDeck MLOps: the platform behind training and inference   Key Responsibilities Set the platform architecture and roadmap for your team, and lead its design and implementation. Lead infrastructure-as-code, automation, and deployment at scale. Make environments reproducible, secure, and fast to change. Own the reliability and operability of the platform, with SRE and Infra Ops. Define standards for CI/CD, observability, and configuration across teams. Raise the engineering bar through mentoring, design and code review, and technical standards.   Your Profile Extensive experience in platform, infrastructure, or SRE engineering at scale. 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 Go, Python, or similar. Deep technical expertise across: Kubernetes and containers in production, including operators Infrastructure-as-code and configuration management (e.g. Terraform, Ansible) CI/CD, release engineering, and GitOps Linux, networking, and cloud or bare-metal infrastructure Experience with GPU, HPC, or bare-metal platforms is a strong plus. Excellent written and verbal communication, including clear design documents and explaining complex trade-offs to technical and non-technical audiences.   What You Bring Platform thinking: Build the foundations other engineers rely on, and make them easy to use. Engineering excellence: Write and review code that sets the standard for correctness, performance, and maintainability. Architectural judgement: Make sound long-term decisions on systems that are hard to change once built. Technical leadership: Influence direction across teams without relying on authority, and grow the engineers around you. Systems thinking: Understand how your area interacts with compute, networking, storage, and the rest of the cloud platform. Ownership: Drive capabilities from design through production, operation, and continuous improvement.   Qualities we look for: Set the standard: Every single day, you spot opportunities to constructively shake things up Inspire the change: There's no blueprint for the future. You'll embrace challenges and change You're real and you're true to yourself: We cherish and celebrate diversity so you'll feel right at home whoever you are and whoever you're talking to, you treat everyone the same.   Why should you join us? What sets us apart is our blend of modern technology, competitive benefits, and an open, welcoming work culture that enables our people to thrive. Here are just some of the great things you can expect from us: 25 days of annual leave A culture that emphasises results over hierarchy, process & ego: we place great emphasis on the quality, ingenuity and creativity of work. Open communication, regular feedback: we value smooth collaboration, direct and actionable feedback, and believe that leading with empathy and a growth mindset makes us better together. Learning Time: we all have dedicated learning time to focus on new skills, projects or