Security Engineer - Sentinel & Defender (Remote)

Tria; City; Hybrid; GBP 45,000 - 55,000; Full time

Job summary

Tria is seeking a Security Engineer to join its Security Operations team, focusing on Microsoft Sentinel and Defender XDR. The role is based in Cardiff with occasional remote/hybrid work.

This permanent position is hands-on, including incident response escalations, deployment and tuning of rules, and collaboration with clients to strengthen security postures. Strong KQL, Defender XDR and Sentinel experience are required, plus the ability to work independently and own tasks.

Qualifications

• Hands-on experience with Microsoft Defender XDR and Sentinel.
• Very good KQL and Advanced Hunting skills.
• Practical experience building, configuring or improving security solutions.
• Familiarity with DevOps and CI/CD pipelines.
• Confidence communicating with clients and explaining technical findings.
• Ability to take ownership of tasks and work independently.

Responsibilities

• Build, deploy and tune Sentinel detection rules using KQL.
• Configure and optimise Microsoft Defender XDR and wider Microsoft 365 security controls.
• Develop automation and response playbooks using Azure Logic Apps.
• Run vulnerability scans and phishing simulations, translating findings into practical recommendations.
• Contribute to development and deployment processes using DevOps and CI/CD.
• Share knowledge with colleagues and participate in an on-call rota.

Skills

Sentinel

Defender XDR

KQL

Advanced Hunting

DevOps

CI/CD

Client communication

Ownership

Independent work

Security clearance

Job description

Tria is seeking a Security Engineer to join its Security Operations team, focusing on Microsoft Sentinel and Defender XDR. The role is based in Cardiff with occasional remote/hybrid work.

This permanent position is hands-on, including incident response escalations, deployment and tuning of rules, and collaboration with clients to strengthen security postures. Strong KQL, Defender XDR and Sentinel experience are required, plus the ability to work independently and own tasks.