Site Reliability Engineer – Mid/Senior (Hybrid, London)

About the role

We are seeking a Site Reliability Engineer to join a small, well‑established infrastructure team in South West London. You will work on a modern, self‑hosted platform that spans Kubernetes, physical servers and automation, with a strong focus on Ubuntu‑based systems. The role offers a hybrid working model with 1–2 days onsite each week.

Key responsibilities

• Administer and maintain Ubuntu Linux server environments.
• Manage self‑hosted Kubernetes clusters and related infrastructure.
• Support on‑premise physical servers and virtualization platforms.
• Administer storage solutions such as NFS, iSCSI and object storage.
• Build and maintain automation using Ansible or similar IaC tools.
• Develop operational tooling with Bash and Python.
• Monitor system health using Prometheus, Grafana, Zabbix or Nagios.
• Investigate and resolve production incidents as part of an on‑call rota.
• Implement security hardening and infrastructure best practices.
• Manage backup and disaster‑recovery processes, including regular testing.
• Support and improve CI/CD pipelines and deployment processes.
• Collaborate with engineering teams to enhance reliability and performance.

Required profile

• Mid‑ to senior‑level experience in Linux systems administration (Ubuntu preferred).
• Hands‑on experience operating production Kubernetes environments.
• Familiarity with networking concepts (TCP/IP, DNS, routing, firewalls).
• Experience with physical servers, virtualization and storage technologies.
• Willingness to participate in an on‑call rotation.

Required skills

• Ubuntu/Linux
• Kubernetes
• Ansible (or other IaC tools)
• Bash scripting
• Python
• Prometheus
• Grafana
• Zabbix
• Nagios
• NFS
• iSCSI
• Object storage
• TCP/IP
• DNS
• Routing
• Firewalls
• Active Directory / Entra ID
• Jenkins
• AWS (S3, Lambda, CloudFront)
• Terraform
• Harvester
• MariaDB
• CI/CD pipelines

What we offer

• Competitive salary plus benefits.
• Hybrid working model (1–2 days onsite).
• Opportunity to work on complex, real‑world infrastructure.
• High ownership within a small, collaborative team.