About the role
About Radiant
Radiant is redefining how AI infrastructure is built.
We design and operate AI-native cloud platforms engineered for sovereignty, performance, and scale. Our infrastructure powers GPU-native workloads, multi-tenant control planes, and high-performance AI systems designed for the most demanding environments.
We are not building a generic cloud. We are building purpose-built AI infrastructure — from powered land, to compute, to software.
As we scale, we're building this organisation from the ground up. We're looking for people who'd rather build the playbook than inherit one — who are comfortable doing the work themselves as well as directing others, and who can adapt as fast as our strategy does. This is a startup model: attitude and adaptability matter more to us than years of experience or the size of the team you've previously managed.
The role
You’ll act as a trusted advisor to managers and employees, providing practical guidance and support across employee relations, performance management, manager coaching and the wider employee lifecycle. Combining hands-on HR expertise with a solutions-focused approach, you’ll help managers navigate complex people matters confidently, ensure consistent and compliant People practices across our global teams, and drive continuous improvement through data, technology and automation as Radiant continues to scale.
What You'll Do
Act as the day-to-day point of contact for employees and managers on HR questions across the full employee lifecycle: onboarding, policy interpretation, benefits, and performance management.
Managing employee relations, providing expert support and recommending appropriate actions to address queries or problems. Proactively reviewing data to spot employee relations trends and suggest solutions, coaching Managers to tackle issues early on.
Serve as the local first line of defense for compliance, ensuring strict adherence to UK labor laws, employment standards, site-specific contracts, and safety protocols.
Help coordinate and run core HR cycles: performance reviews, compensation planning, and engagement surveys, for the London office.
Draft, review and interpret employment contracts, variations and restrictive covenants.
Own the review and update of people policies and the employee handbook, keeping them compliant and easy to use.
Track legislative changes, including the Employment Rights Act reforms, and lead their implementation.
Maintain accurate employee records and HR systems, and help build out People processes and documentation as the team grows.
Compliance
Help ensure compliance with employment law and best practice across the UK, Europe and the US, in consultation with the HRBP and external counsel as needed.
Compliance and risk. Make sure People processes meet UK employment law, data protection requirements, our ISO requirements and Radiant's own policies. Ensure the team keeps policies and manager guidance up to date as legislation changes.
Immigration and visas
Manage Skilled Worker and other visa applications from assessment to approval, partnering with our external immigration lawyers.
Advise on global mobility as we expand into Europe.
Workforce planning
Partner with leaders to build headcount plans aligned to business priorities and budget.
Advise on organisation design, team structures and spans of control as teams scale.
Use people data from HiBob and Ashby to inform hiring, retention and capacity decisions.
Performance
Help design and run the performance reviews and calibration process.
Support managers to set clear goals, give regular feedback and manage underperformance through fair, well-documented processes.
Link performance outcomes to development, promotion and reward decisions.
What you'll bring
5+ years in a People Partner, HR Business Partner or senior generalist role, ideally in a scaling tech or high-growth business.
Deep, current knowledge of UK employment law and confidence applying it to real situations.
CIPD Level 5 or 7, or an employment law qualification.
Confident and knowledgeable enough to manage employee relations issues independently, with sound judgement on when to escalate.
A proactive, solutions-oriented approach and a track record of taking initiative.
Exposure to multi-jurisdiction employment matters is an advantage.
Strong technical capability and data literacy, and comfort using data and technology to inform decisions and drive efficiency