Senior Quality Engineer — Investigate & Respond

About Us Sophos is a cybersecurity leader defending 600,000 organizations globally with an AI-driven platform and expert-led services. Sophos meets organizations wherever they are in their security maturity and grows with them to defeat cyberattacks. Its solutions combine machine learning, automation, and real-time threat intelligence with frontline human expertise from Sophos X-Ops to deliver advanced, 24/7 threat monitoring, detection, and response. Sophos offers industry-leading managed detection and response (MDR) alongside a comprehensive portfolio of cybersecurity technologies — including endpoint, network, email, and cloud security, extended detection and response (XDR), identity threat detection and response (ITDR), and next-gen SIEM. Together with expert advisory services, these capabilities help organizations proactively reduce risk and respond faster, with the visibility and scalability needed to stay ahead of evolving threats. Sophos goes to market with a global partner ecosystem, including Managed Service Providers (MSPs), Managed Security Service Providers (MSSPs), resellers and distributors, marketplace integrations, and cyber risk partners, giving organizations the flexibility to choose trusted relationships when securing their business. Sophos is headquartered in Oxford, U.K. More information is available at www.sophos.com . Role Summary We are looking for a Senior Quality Engineer to champion quality across the Investigate & Respond product area. In this role, you will work autonomously across services, APIs, and user-facing workflows — helping teams catch issues early, build meaningful automated coverage, and deliver reliable customer experiences. What You Will Do: Own and evolve the team's quality strategy across functional, integration, API, and end-to-end testing. Design, implement, and maintain automated test coverage using established frameworks and practices. Partner with engineers and product managers — from refinement through release — to identify risk, sharpen acceptance criteria, and build quality into every stage of delivery. Test complex workflows spanning distributed services, asynchronous processing, APIs, and web applications. Investigate production issues and customer-reported defects; translate findings into regression coverage and process improvements. Raise quality risks early and advocate for pragmatic solutions that protect the customer experience. Improve test reliability, execution speed, observability, and developer feedback loops. What You Will Bring: 5+ years of experience in software quality engineering, SDET, or a closely related role. Hands-on experience designing and maintaining automated tests across API, service, and UI layers. Experience with Python and pytest for test automation. Experience with modern testing frameworks and automation practices. Strong API testing experience. The ability to build test strategies for ambiguous, cross-service, or high-risk changes. A self-directed working style — you take initiative, drive investigations to completion, and know when to pull others in. Clear, direct communication and comfort influencing decisions across engineering and product teams. Familiarity with CI/CD pipelines, test reporting, and test environment management. Nice to Have GraphQL experience. Familiarity with Go testing ecosystems. Hands-on experience with Playwright. Experience writing or reviewing Go code. Experience in cybersecurity, SaaS, or complex enterprise products.