System Administrator jobs in United Kingdom

National Energy System Operator’s (NESO) strength lies in our people. Together, we’re shaping the future where clean, affordable energy is accessible for all. Every day is an opportunity to make a real difference, accelerating the progress of sustainable GB energy, keeping people connected and society thriving as we create a brighter tomorrow.

We are seeking a highly skilled and experienced Lead Platform Architect to further build upon existing design and maintain the robust and scalable network and infrastructure architecture for our OpenShift platform. This is a critical role that shapes foundation of our application delivery, ensuring high availability, performance, and security for all products and services hosted on the platform.

As a Platform Architect, you will work with our network and infrastructure providers to structure layout of on‑premises OpenShift platform.

This role can be based in Warwick or Wokingham, and we continue to offer hybrid working from office and home. We are open to full time and part time applicants, as well as flexible working arrangements.

• Architectural Design: Lead the design of the end-to-end infrastructure and network architecture for our OpenShift platform, including networking, storage, compute, and security components.
• OpenShift Expertise: Serve as the subject matter expert on OpenShift infrastructure and networking, including OVN-Kubernetes, Open vSwitch, SDN, and various CNI plugins.
• Network Strategy: Define and implement the network topology and security policies for the OpenShift cluster and its hosted applications, including ingress/egress routing, load balancing, and firewall rules.
• Security and Compliance: Design and enforce security best practices within the infrastructure and network layers, ensuring compliance with industry standards and internal policies. This includes implementing network segmentation, micro‑segmentation, and zero‑trust principles.
• Performance and Scalability: Optimize the infrastructure and network for performance and scalability, ensuring the platform can handle increasing workloads and traffic.
• Automation: Drive the automation of infrastructure provisioning, configuration, and management using Infrastructure as Code (IaC) tools such as Terraform, Ansible, and GitOps workflows.
• Troubleshooting: Act as the escalation point for complex infrastructure and network issues, providing expert‑level troubleshooting and root cause analysis.
• Collaboration: Work closely with OpenShift platform engineers, application development teams, security teams, and operations teams to ensure seamless integration and alignment of architectural goals.
• Mentorship: Mentor and guide junior engineers, sharing knowledge and fostering a culture of technical excellence.
• Roadmap and Innovation: Stay abreast of emerging technologies and industry trends in cloud‑native networking and infrastructure, and contribute to the long‑term strategic roadmap for the platform.

• Proven experience in a senior infrastructure or network architecture role, with a strong focus on cloud‑native platforms.
• Deep expertise in Red Hat OpenShift, including its core components and underlying infrastructure.
• Extensive experience with Kubernetes networking concepts (CNI, Services, Ingress, Network Policies).
• Solid understanding of network protocols and technologies (TCP/IP, DNS, BGP, VPNs, firewalls).
• Hands‑on experience with public cloud providers (e.g., AWS, Azure, GCP) and their networking services.
• Proficiency in Infrastructure as Code (IaC) tools like Terraform or CloudFormation.
• Experience with configuration management tools like Ansible.
• Strong scripting skills (e.g., Python, Bash).
• Excellent problem‑solving, communication, and collaboration skills.

• Microservices Architecture: Experience designing and implementing network and infrastructure solutions for microservices‑based applications. This includes knowledge of service mesh technologies (e.g., Istio, Linkerd) and API gateways.
• Red Hat Technologies: Experience with other Red Hat technologies such as Red Hat Enterprise Linux (RHEL), Red Hat Ansible Automation Platform, Red Hat Satellite, or Red Hat Ceph Storage.
• Certifications: Holding certifications like Red Hat Certified Architect (RHCA) or Red Hat Certified Engineer (RHCE) is a significant plus.
• Familiarity with CI/CD pipelines and GitOps methodologies.
• Knowledge of monitoring and observability tools (e.g., Prometheus, Grafana, ELK stack).
• A passion for open‑source technologies and community contributions.

Don’t meet every single requirement? Studies have shown that women and people of colour are less likely to apply for jobs unless they meet every single qualification. At NESO, we are committed to building a diverse, inclusive, and authentic workplace for everyone. So, if you’re excited about this role but your experience or qualifications don’t match the job description exactly, we encourage you to apply anyway. You might just be the right person for our growing business in this role or another one.

A competitive salary between £75,000 - £85,000pa – dependent on experience and capability.

As well as your base salary, you will receive a bonus of up to 15% of your salary for stretch performance, 28 days annual leave as standard, and a competitive contributory pension scheme where we will double match your contribution to a maximum company contribution of 12%.

As we work towards creating a cleaner, greener, and more affordable future for all, we also work towards creating a place for our teammates to belong, with professional and personal growth and positive well‑being.

• Full support and career‑development resources to expand your skills, enhance your expertise, and maximise your potential along your career journey.
• A diverse and inclusive community of belonging, where teammates are empowered to bring ideas to the table.
• Generous Total Rewards Plan – comprising of health, finance and wealth, work/life balance, and career benefits.

National Energy System Operator’s (NESO) mission is to facilitate the decarbonisation of Great Britain’s energy network and ensure the delivery of reliable, affordable, and clean electricity for consumers. We work with stakeholders across the whole energy industry to plan for future network needs, using a wider adoption of technology and changes in consumer behaviour, as well as ensuring we have the right markets, networks, and frameworks in place, to transform the way we operate tomorrow.

Join us, and let’s energise progress.

Our energy, our future, together.

In Autumn of 2024, the ESO transitioned to National Energy System Operator, or NESO for short. Previously denoted as the Future System Operator (or FSO), the new National Energy System Operator is the independent body responsible for planning Great Britain’s electricity and gas networks and operating the electricity system.

The ESO, including all of its existing roles, are now at the heart of the new National Energy System Operator. As NESO, we will build on our existing roles, capabilities, and ways of working significantly to create an organisation the energy system and its users’ need. Our new capabilities will enable us to look across vectors, including electricity, natural gas and hydrogen, and crucially consider the trade‑offs between them.

The organisation is set up as a public corporation with its own Board of independent directors, with complete operational independence from government, the regulator and any and all commercial interest. As was the ESO, NESO will be licenced and regulated by Ofgem through price control agreements and obligated to identify optimal solutions to system operations and planning in the most sustainable, affordable and secure way for all.

We work towards the highest standards in everything we do, including how we support, value and develop our people. Our aim is to encourage and support employees to thrive and be the best they can be. We celebrate the difference people can bring into our organisation, and welcome and encourage applicants with diverse experiences and backgrounds, and offer flexible and tailored support, at home and in the office.

We’re committed to building a workforce that represents the communities we serve, and a working environment in which each individual feels valued, respected, fairly treated, and able to reach their full potential.