Defence ArcSight SIEM Engineer - Onsite (Basingstoke)

At CGI, we're redefining how technology protects the nation. As an ArcSight SIEM Engineer, you'll play a vital role in a major defence programme-modernising secure data platforms, driving automation, and strengthening the UK's cyber resilience.

Working at the forefront of national security, you'll design and support cutting-edge systems that enable faster, smarter threat detection and decision-making. You'll be part of a close-knit team that thrives on collaboration, innovation, and technical excellence-where you'll have the freedom to take ownership of your work, the opportunity to create lasting impact, and the support of a global organisation committed to your growth.

CGI was recognised in the Sunday Times Best Places to Work List 2025 and has been named a UK 'Best Employer' by the Financial Times. We offer a competitive salary, excellent pension, private healthcare, plus a share scheme (3.5% + 3.5% matching) which makes you a CGI Partner not just an employee.

We are committed to inclusivity, building a genuinely diverse community of tech talent and inspiring everyone to pursue careers in our sector, including our Armed Forces, and are proud to hold a Gold Award in recognition of our support of the Armed Forces Corporate Covenant.

Due to the secure nature of the programme, you will need to hold UK Security Clearance (HLC/DV). This is a full time onsite role in Basingstoke (no hybrid or remote working).

In this role, you will be instrumental in modernising and maintaining key defence platforms, ensuring data collection and analysis systems are secure, efficient, and future ready.

Working within a collaborative client site environment, you will develop, configure, and optimise ArcSight SIEM toolsets, ensuring the seamless integration of new capabilities to support national security operations. You will also automate release and deployment processes to improve quality and delivery speed, while maintaining rigorous standards for documentation and compliance.

Key responsibilities:

• Develop & optimise: modernise data collection, processing, and storage systems using tools like Kafka, Kubernetes, and Zookeeper
• Automate & enhance: streamline release processes using Ansible and Azure DevOps
• Configure & maintain: support and troubleshoot ArcSight SIEM components (filters, SmartConnectors, ESM)
• Collaborate & align: translate security requirements into technical solutions with internal teams
• Document & support: produce and maintain technical and support documentation

You should bring strong systems engineering experience with a focus on security, automation, and SIEM technologies, ideally in defence or other secure environments.

Essential skills and experience:

• Hands on ArcSight SIEM configuration, support, and troubleshooting
• Strong experience in RHEL and Windows environments
• Automation using Ansible and Azure DevOps
• Familiarity with Kafka, Kubernetes, and distributed systems
• Strong communication skills (written and verbal)
• Understanding of data engineering concepts (SQL or Big Data)
• Scripting skills (PowerShell, Bash) desirable
• Active HLC/DV clearance required

We also offer a competitive salary, a pension plan, private health care and a share scheme which makes you a CGI Partner.