Senior Site Reliability Engineer Head Office

Once For All is a high-growth, cloud-based, SaaS subscription business. Our technology helps our customers to manage their supply chain governance, risk management and compliance. We work across public and private sector and have over 250k customers across the UK across 20 different sectors including construction, transport, retail, hospitality education, facility and property management, manufacturing, local and central government.

Join our Reliability and Platform group partnering with 10 Agile SCRUM teams to scale and harden a suite of microservices on Microsoft Azure. You will own production reliability for tier-1 services, set and track SLOs, automate operations, and lead incident response to keep our next-generation Supplier Risk Assessment platform fast, secure, and available. This role is fully remote role.

• Define SLOs, SLIs, and error budgets for critical services.
• Architect resilient multi-region and zone-aware workloads on Azure and AKS.
• Build infrastructure as code with Terraform or Bicep. Enforce policy as code.
• Design safe releases with progressive delivery, automated rollbacks, and feature flags.
• Lead on-call rotations, incident response, postmortems, and corrective actions.
• Implement end-to-end observability: metrics, logs, traces, dashboards, alerts.
• Plan capacity, tune performance, and optimize cost without impacting reliability.
• Secure the stack with Managed Identity, Key Vault, workload identity, and network segmentation.
• Establish backup, disaster recovery, and tested restore procedures with clear RPO and RTO.
• Mentor engineers and raise reliability standards across product teams

• 10+ years in SRE, platform, or production-facing engineering roles running large-scale systems.
• 7+ years hands‑on with Microsoft Azure: AKS, Front Door or Application Gateway, VNets, Private Link, Key Vault, Monitor, Log Analytics, Application Insights, Service Bus, Storage, SQL or Cosmos DB.
• 6+ years operating Kubernetes in production, including at least 3 years on AKS (network policies, Pod Disruption Budgets , HPA/VPA, node pools, upgrade playbooks).
• 5+ years infrastructure as code with Terraform or Bicep and Git‑based workflows.
• 5+ years designing observability and SLO‑based alerting using Open Telemetry and Kusto queries.
• 4+ years running canary or blue‑green deployments in Azure Dev Ops or Git Hub Actions.
• Proven incident command experience with measurable MTTR and MTTD improvements.
• Strong automation skills in Python or Go, plus Bash and Power Shell.
• Solid understanding of security hardening, container image scanning, SBOM, and least privilege.
• Experience with performance testing, p95 and p99 tuning, caching and connection pool strategies.

• Multi‑tenant SaaS and data sovereignty patterns.
• Service mesh, eBPF, or advanced traffic shaping.
• Compliance and audit trail design.
• Fin Ops practice with cost per request or per tenant KPIs.

• Health and Wellbeing:
  Private Medical Insurance or wellness fund, 24/7 Employee Assistance Programme.
• Financial Benefits:
  
  Pension, Life Assurance (3x salary).
• Time Off: 25 days holiday + 8 bank holidays, holiday purchase scheme (+5 days), paid and unpaid volunteering days.
• Growth and Development:
  Ongoing CPD, team offsites, and company events.
• Everyday Perks:
  Home office budget, high‑spec laptop and peripherals.
• Work Setup:
  Fully remote within UK time zones, optional access to our Basingstoke office.

Azure, AKS, Terraform or Bicep, Azure Dev Ops or Git Hub Actions, Docker, Helm, Service Bus, Storage, SQL Server, Cosmos DB, Key Vault, Azure Monitor, Log Analytics, Application Insights, Prometheus, Grafana, Open Telemetry, Feature flagging tools.

• Intro and role overview with Talent.
• Technical deep dive on Azure and AKS architecture.
• Practical exercise: propose SLOs and an alert plan for a sample service, plus a release safety plan.
• Culture and collaboration interview with Engineering.