Senior SIEM Engineer - Microsoft Sentinel & XDR

About the role

EY GDS Spain is looking for a Senior SIEM Engineer to join its Cyber Security team in Malaga, within a Threat Detection & Response (TDR) environment focused on Microsoft Sentinel and XDR. You will design, integrate and operate SIEM use cases and automations, support clients in running modern cloud-native security platforms, and take part in digital transformation projects.

Key responsibilities

• Integrate data sources into Microsoft Sentinel (cloud, identity, endpoint, network and on-premises) and ensure data quality and normalization.
• Design, implement and operate analytics rules, SIEM use cases and hunting queries (KQL; SPL experience is a plus).
• Develop and maintain playbooks and automations with Azure Logic Apps to standardise response workflows.
• Act as technical subject matter expert for SIEM and Microsoft Sentinel/XDR, guiding stakeholders hands-on.
• Optimise SOC operations, including tuning, false-positive reduction and performance, and contribute to documentation, repeatable deployments and detection-as-code.

Required profile

• 2 to 4+ years of experience in SIEM engineering (design, onboarding, use case development, tuning and operations), ideally with Microsoft Sentinel.
• Hands-on experience with Azure, Windows/Linux and scripting (e.g. Python, PowerShell, Bash), and automation concepts.
• Experience building or operating SOAR-style automations (Logic Apps / playbooks) in a security operations context.
• English at least B2 (written and spoken).

Required skills

• Cloud security concepts, SIEM architectures and the MITRE ATT&CK framework.
• Ideal: Splunk (SPL, data onboarding, correlations, dashboards) and/or open-source SIEM (Elastic/ELK, Wazuh).
• Relevant certifications such as SC-200 or AZ-500 are a plus.

What we offer

• A hybrid work model.
• Tailored training and development programmes.
• Wellness initiatives, including psychological support sessions.
• Volunteering opportunities and recognition programmes for performance.