Contract Senior Security Engineer: Cloud, SIEM & IR

Flagstone Group Ltd; Greater London; On-site; GBP 70,000 - 100,000; Part time

Job summary

Flagstone Group Ltd is seeking a senior security engineer to own cloud security, detection tooling, and incident response across Azure. The role focuses on sustaining and improving our security stack, coordinating pentests, and guiding remediation with engineering squads.

You will work in a fintech context, applying Terraform/Bicep for security tooling, and contribute to secure data handling and AI workflow protections. This is a contract role with immediate impact.

Qualifications

• Hands-on cloud security engineering experience in fintech or financial services.
• Experience operating and improving SIEM and security tooling in Azure environments.
• Experience coordinating penetration tests and remediation with engineering teams.

Responsibilities

• Own alerting and monitoring capability during transition and keep detection steady.
• Maintain and tune Microsoft Sentinel deployment and reduce alert noise.
• Coordinate penetration test engagements and remediation with squads.

Skills

SIEM experience

Azure security

Terraform

KQL

Threat modelling

Vulnerability remediation

AI security

Incident response

Security operations

Education

SC-200 certification

Tools

Microsoft Sentinel

Defender for Cloud

Entra ID

Terraform

Bicep

Job description

Flagstone Group Ltd is seeking a senior security engineer to own cloud security, detection tooling, and incident response across Azure. The role focuses on sustaining and improving our security stack, coordinating pentests, and guiding remediation with engineering squads.

You will work in a fintech context, applying Terraform/Bicep for security tooling, and contribute to secure data handling and AI workflow protections. This is a contract role with immediate impact.