Senior Site Reliability Engineer

About the role

We are looking for a Senior Site Reliability Engineer to join a well‑established B2B SaaS company in Milton Keynes. The role offers up to £70,000 plus bonus and on‑call allowance, with a hybrid working model (two days on‑site per week). You will be responsible for building stability, responding to live incidents, maintaining systems, and driving the adoption of new tooling and processes as part of a major platform transformation, with a clear path to a team‑lead position.

Key responsibilities

• Provision, configure and automate servers, networks and application lifecycles using Terraform, Kubernetes and related technologies.
• Monitor application performance and reliability with Datadog and other observability tools.
• Design and implement new processes to improve incident response and recovery.
• Own incident resolution and drive down MTTR, incident frequency and on‑call toil.
• Participate in an on‑call rota and ensure timely response to incidents.
• Identify automation opportunities and implement reliability improvements.

Required profile

• Previous experience as a Site Reliability Engineer or in a similar cloud/infrastructure role within a customer‑facing environment (SaaS or MSP).
• Strong hands‑on experience with Microsoft Azure and on‑premise virtual machines.
• Proficiency with Infrastructure as Code (Terraform), container orchestration (Kubernetes or AKS) and monitoring/observability tools (Prometheus, Grafana, Datadog, Azure Monitor).
• Demonstrated ability to introduce new tools and processes and achieve adoption across development and support teams.
• Excellent communication skills for interacting with internal teams and external customers.
• Solid networking knowledge across cloud and on‑premise environments.
• Windows or Linux systems administration experience (Linux preferred).
• Experience using AI tools to enhance efficiency.

Required skills

• Microsoft Azure
• On‑premise virtual machines
• Terraform
• Kubernetes / AKS
• Prometheus
• Grafana
• Datadog
• Azure Monitor
• Linux administration
• Windows administration
• Networking (cloud and on‑premise)
• Infrastructure as Code
• Container orchestration
• Incident management
• Automation

What we offer

• Salary range £65,000 – £75,000 per year
• Performance bonus and on‑call allowance
• Hybrid working model (2 days on‑site)
• Opportunity to progress to a team‑lead role as the team expands
• Exposure to cutting‑edge SaaS platform transformation projects