Security Engineer II

Tesco UK • Welwyn Garden City • Hybrid • Full-Time • Working hours 36 • Apply by 04-May-2026

As a Cyber Security Detection Engineer, you will lead the development, implementation, and continuous improvement of Tesco's cyber security detection capability. You will be required to understand the changing threat landscape, see opportunities for improvement in existing detections, establish new detections, and ensure appropriate detection coverage for the organisation. You will work closely with multiple teams, including security operations, engineering, and risk & compliance, in a fast paced and agile environment.

What is in it for you

We're all about the little helps. That's why we make sure our Tesco colleague benefits package takes care of you - both in and out of work. Click Here to find out more!

• Annual bonus scheme of up to 20% of base salary
• Holiday starting at 25 days plus a personal day (plus Bank holidays)
• Private medical insurance
• 26 weeks maternity and adoption leave (after 1 years' service) at full pay, followed by 13 weeks of Statutory Maternity Pay or Statutory Adoption Pay, we also offer 4 weeks fully paid paternity leave
• Free 24/7 virtual GP service, Employee Assistance Programme (EAP) for you and your family, free access to a range of experts to support your mental wellbeing

You will be responsible for

Responsible for developing and driving the cyber security detection capability both day-today and strategically for the Tesco Group. You are expected to seek out effective and comprehensive detection logic and capability, ensuring detections are robust and not brittle, thoroughly tested, and that alerts and supporting information is available to and understood by operational cyber security teams. You are expected to put the needs of operational teams and incident responders at the centre of your development work, ensuring detections and alerts are relevant, of value, and have practical response steps. You will need to ensure detection capability is fit for both onpremises, private and public cloud environments, working at significant scale, and across a diverse range of asset types. In addition, you may provide support during cyber security incidents, participate in threat hunts, and work with other security teams to deliver automation and standardisation to improve efficiency and response.

You will need

Relevant Operational skills:

• Ability to assess and validate information from various sources on cyber and informational security threats to business
• Ability to analyse and identify significance of processed intelligence to identify trends, threat actor TTPs and potential capabilities
• Ability to break down and translate information into tangible actionable data

Secure & Test-Driven Engineering:

• Understanding of cyber security threat frameworks such as MITRE ATT&CK, Lockheed Martin Killchain etc. 2
• Ability to specify/implement processes to maintain required level of security for a component/product/system during its lifecycle
• Proficient at detection development lifecycle covering all reasonable positive and negative test cases
• Ability to conduct code reviews of existing content and processes to identify and enhance or mitigate security issues
• Contribute to security evaluation of or testing of threat/vulnerabilities faced by systems
• Applies recognised evaluation/testing methodologies, tools and techniques to signature development / reviews, suggesting new ones where appropriate

Research:

• Ability to quantify and define research goals to generate worthwhile relevant detection ideas for further testing and exploration
• Ability to summarise findings or technical information to be disseminated with wider teams, factoring in business knowledge and summaries

Experience relevant for this role:

• Ability to develop queries and enable robust detection of threats
• Working knowledge of Windows, macOS or Linux operating systems
• Ability to work independently as well as part of a team
• Understanding of modern attacker TTPs
• Translate threat intelligence into actionable detection logic
• Solid grasp of detection technologies
• A broad understanding of security concepts; an interest and passion for cyber security
• An analytical approach; ability in problem solving and comfortable working on production systems at scale
• Query languages such as KQL or SPL
• Experience developing and maintaining basic automation scripts (e.g., Bash, Python, Batch, PowerShell etc.)

Desirable Skills and Experience:

• Knowledge of cloud infrastructure, cloud security and cloud APIs a plus
• Knowledge of attacker tools and evasion techniques within offensive engineering
• Working knowledge of at least one major programming language, including scripting languages like Python and PowerShell
• Experience of developing detections as code

Desirable Certifications:

• One or more from: CompTIA Security+, GIAC, CEH, SSCP. Where appropriate other industry relevant certifications will be considered

About us

Our vision at Tesco is to become every customer's favourite way to shop, whether they are at home or out on the move. Our core purpose is 'Serving our customers, communities and planet a little better every day'. Serving means more than a transactional relationship with our customers. It means acting as a responsible and sustainable business for all stakeholders, for the communities we are part of and for the planet.

We are proud to have an inclusive culture at Tesco where everyone truly feels able to be themselves. At Tesco, we not only celebrate diversity, but recognise the value and opportunity it brings. We're committed to creating a workplace where differences are valued, and make sure that all colleagues are given the same opportunities. We're proud to have been accredited Disability Confident Leader and we're committed to providing a fully inclusive and accessible recruitment process. For further information on the accessibility support we can offer, please click here.

We're a big business and we can offer a range of diverse full-time & part-time working patterns across our many business areas, which means that we can find something that works for you. We work in a more blended pattern - combining office and remote working. Our offices will continue to be where we connect, collaborate and innovate. If you are applying internally, please speak to the Hiring Manager about how this can work for you - Everyone is welcome at Tesco.