As a Senior Security Analyst, you’ll play a key role in strengthening and evolving security across our branch systems. You’ll help drive improvements to our IT security controls using a layered defence approach, ensuring systems remain secure, resilient and compliant. You’ll take the lead on identifying and managing vulnerabilities, coordinating patching and upgrades, and investigating security incidents. You’ll also support the wider team by providing technical guidance, mentoring colleagues and helping shape how we deliver secure, reliable technology. This is a hands-on and collaborative role where you’ll work closely with teams across Booker and Tesco, as well as third-party partners, to keep our operations running smoothly and securely. Drive and improve IT security controls across Booker systems Plan and manage patching and software updates in line with security standards Identify, assess and remediate vulnerabilities, risks and security gaps Lead investigations into security incidents and provide clear recommendations Act as a technical escalation point for complex security issues Ensure systems are secure, compliant and accurately maintained Support day-to-day service delivery and coordinate workload across the team Lead delivery of small to medium security projects and improvements Maintain high-quality documentation aligned to audit and compliance standards Build strong relationships with stakeholders, suppliers and colleagues Provide mentoring, guidance and line management support to junior team members Experience working in IT security within a production or enterprise environment Hands-on knowledge of security technologies such as firewalls, SIEM, endpoint protection or MDM tools Understanding of network security, authentication and threat mitigation Experience supporting and securing Linux-based systems Strong problem-solving skills and the ability to make decisions in fast-paced environments Excellent communication and stakeholder management skills Knowledge of governance, risk and compliance principles A collaborative and inclusive approach to teamwork and leadership Ability to balance immediate operational priorities with longer-term security improvements