Operational Assurance Test (OAT) Lead

• Location: Winchester, Hampshire, United Kingdom

345 Technology helps organisations modernise, integrate and optimise their technology landscape through cloud, data, AI and enterprise integration services. We are seeking an experienced Operational Assurance Test (OAT) Lead to support a critical programme of work focused on resilience, disaster recovery, observability and operational readiness.

As the Operational Assurance Test (OAT) Lead, you will be responsible for designing and executing end-to-end operational testing across business-critical systems and integrations. You will ensure that solutions are resilient, recoverable and supportable under real-world conditions, including failures, outages and disaster recovery scenarios.

This is a hands‑on role requiring strong technical testing experience alongside the ability to work with business and delivery teams to identify operational risks and improve system readiness.

The role is offered on an initial 3 month fixed term contract.

• Design end-to-end Operational Acceptance Testing (OAT) scenarios based on business processes and customer journeys.
• Execute OAT testing covering:
  • System resilience
  • Disaster Recovery (DR)
  • Observability and monitoring
  • Recovery procedures
  • Operational supportability
• Planned failures
• Partial outages
• Recovery and restoration activities
• Conduct failure simulation testing, including API failures, integration failures and infrastructure-related incidents.
• Verify resilience across end‑to‑end business and integration flows.

• Assess DR readiness for business‑critical applications and services.
• Design, execute and report on failover and failback testing.
• Validate recovery objectives and operational processes.
• Identify gaps and risks that could impact service continuity.

• Identify opportunities for operational test automation.
• Prioritise automation initiatives based on:
  • Business criticality
  • Execution frequency
  • Regression value
  • Risk reduction
• Ensure appropriate safety, governance and control measures are embedded within testing activities.
• Establish repeatable OAT frameworks and best practices.

• Govern OAT execution across multiple projects and work streams.
• Highlight operational risks, resilience weaknesses and testing hotspots.
• Produce clear reporting and recommendations for stakeholders.
• Drive the adoption of OAT best practices across delivery teams.

• Proven experience delivering Operational Acceptance Testing (OAT) within enterprise environments.
• Strong understanding of disaster recovery, business continuity and resilience testing.
• Experience testing APIs, integrations and distributed systems.
• Knowledge of observability platforms, monitoring solutions and support processes.
• Experience with failure simulation, resilience engineering or chaos testing approaches.
• Strong stakeholder management and communication skills.
• Experience working within cloud‑based and highly integrated environments.
• Ability to work independently and deliver outcomes in a fast‑paced consultancy setting.
• Experience with Microsoft Azure environments.
• Knowledge of Azure Integration Services, Mule Soft or enterprise integration platforms.
• Experience of automated testing frameworks and Dev Ops practices.
• Familiarity with ITIL, service management or operational readiness frameworks.

• Opportunity to work on a high‑profile transformation programme.
• Collaborative and innovative consultancy environment.
• Exposure to leading cloud, integration and AI technologies.
• Flexible and hybrid working arrangements.