Senior Security Engineer - Detection Engineering

Location: Welwyn Garden City, United Kingdom; hybrid working with 60% of the week spent collaborating at office locations or local sites and the remainder remotely.

Company

hirify.global develops technology supporting Tesco’s retail ecosystem, mobile network, customer services, and global operations.

What you will do

• Design, build, deploy, and improve high-reliability security capabilities across Tesco’s technology estate.
• Translate threat and risk signals into automated, testable detection and response capabilities.
• Champion secure, test-driven engineering through code quality, automated testing, peer review, and repeatable delivery.
• Evaluate AI-assisted and automation-driven approaches to improve detection development, tuning, and quality assurance.
• Coach junior engineers and promote pragmatic security design and modern development practices.
• Collaborate with Security Operations, Threat Intelligence, platform teams, and product and engineering stakeholders.

Requirements

• Experience delivering production-grade solutions through design, build, testing, deployment, operation, and continuous improvement.
• Evidence of writing clean, maintainable code or scripts with attention to reliability, scalability, and operational support.
• Experience developing custom detections and working with data at product scale.
• Understanding of threat-aware design, secure defaults, automated testing, disciplined change control, and detection and response workflows.
• Ability to convert adversary behaviour hypotheses into effective detections, reduce noise without compromising visibility, and maintain detection quality over time.
• Curiosity, continuous learning, mentoring ability, and a collaborative approach that supports diverse perspectives.

Nice to have

• Cloud and container security knowledge, including hardening cloud-native services.
• Applied AI for cyber defence, AI governance, and responsible AI awareness.
• Experience with GitHub, Jira, Zendesk, xMatters, or querying languages such as SPL, KQL, and SQL in a security environment.
• Retail technology awareness and understanding of how customer journeys and store and online operations shape risk.
• Knowledge of security evaluation, functionality testing, security architecture, and secure-by-design product methodologies.

Culture & Benefits

• Hybrid working model balancing office or local-site collaboration with remote work.
• Annual bonus scheme of up to 20% of base salary.
• At least 25 days of holiday plus a personal day and bank holidays.
• Private medical insurance and a free 24/7 virtual GP service.
• Paid maternity, adoption, and paternity leave, alongside employee assistance and wellbeing support.
• Inclusive and accessible recruitment process with support available for applicants who need adjustments.