Jefferson Sousa

Experienced Systems Security Engineer (Senior ICT Cloud & Security Engineer) with over 7 years of managing and securing Microsoft infrastructure, hybrid Active Directory, and Entra ID environments. Achieved 99.9% uptime and led security remediation projects that reduced vulnerabilities by 73.5%, demonstrating tangible results in complex environments supporting more than 10,000 identities.

Cloud Security Engineer Associate at Food Safety Authority of Ireland (2025-12 – Present)

• Hybrid Identity Orchestration: Achieved seamless synchronisation between on-premises Active Directory and Microsoft Entra ID (Azure AD) through Connect/Cloud Sync; integrated AWS IAM Identity Centre and added Conditional Access, Privileged Identity Management, and MFA to enhance security for over 1,000 identities, demonstrating strong identity and access management (IAM) and IGA capabilities.
• Technical Debugging & Engineering: Connected infrastructure and backend engineering by using IDEs and log parsing to troubleshoot Okta, SAML, and OIDC issues, diagnosing and fixing deep-system failures to enhance the resolution process.
• Implemented Terraform-based automation for IAM strategy and access management within Azure, streamlining RBAC design and least privilege protocols to align with zero trust principles across cloud environments using Infrastructure as Code.

Cloud Security Engineer Associate at Eir Business (old Eir evo) (2025-08 – 2025-12)

• Managed Tier 2/3 identity services for over 10,000 users, focusing on identity governance and security, which underscores your proven success in high-availability and compliance projects.
• Operational Excellence & ITSM: Improved ServiceNow workflows and integrated Microsoft Sentinel and XDR tools, resulting in an 85% increase in SLA compliance; delivered specialised Level 3 remote support via TeamViewer Tensor to troubleshoot critical infrastructure issues.
• Legacy & Hybrid Messaging: Managed critical on-premises Exchange Server infrastructure to ensure high availability and optimal performance for a global user base, ensuring smooth mail flow and database reliability.

Cloud Security Automation Specialist (SIEM / SOAR) at The Dean Group (2023-11 – 2025-05)

• Security Orchestration (SOAR): Led the automation of incident response by integrating ServiceNow, Microsoft Sentinel (SIEM), and Azure Logic Apps; developed detailed automated runbooks that standardised response procedures, shortening the mean-time-to-remediate (MTTR) and improving incident management, change management, and problem management.
• Enterprise Continuity & Disaster Recovery: Designed and implemented BCP/DR plans for over 100 critical systems; coordinated on-premises and Azure workloads to align fully with enterprise security policies and zero-trust principles.
• Resilient Infrastructure Design: Used Azure Site Recovery (ASR) and Geo-Redundant Storage (GRS) to deploy high-availability recovery solutions, ensuring 24/7 operational resilience; initiated automated failover testing protocols to ensure uninterrupted operations during large-scale cloud migrations.

Cloud Integration Specialist – (AWS & Opera) at Louis Fitzgerald Group (2022-08 – 2023-11)

• Proactively identified and mitigated non-human identity risks, such as service accounts and API keys, reducing the potential attack surface by 75%.
• Enterprise Infrastructure Lead: Provided technical leadership, overseeing high-availability operations for Microsoft 365 (Exchange/SharePoint) and Windows Server (2019-2022); acted as Tier 3 SME, maintaining a top First-Contact Resolution rate for complex outages.
• Implemented service improvement initiatives that enhanced incident response times by 85%, aligning with ITIL best practices and improving overall service delivery.
• Configured and managed Microsoft Defender XDR solutions to enhance endpoint security and threat detection capabilities across the organisation.

Systems Support & Infrastructure Team Lead at Accor (2018-09 – 2022-07)

• Technical Training & Workforce Readiness: Spearheaded comprehensive IT infrastructure and security protocol training for all technical new hires, accelerating onboarding efficiency by 75% and drastically reducing initial support ticket queues.
• Service Delivery & SLA Governance: Directed engineering mentorship programs and system response frameworks across regional channels, successfully maintaining a consistent 100% SLA compliance threshold.
• Infrastructure Deployment & OS Stability: Orchestrated the secure configuration, imaging, and hardware deployment of over 65% of regional Windows-based endpoints, improving core system stability by 30% during peak operational hours.
• Lifecycle Management & Vendor Escalation: Managed full-lifecycle inventory auditing for mission-critical enterprise hardware and acted as the primary engineering point of contact for complex third-party vendor escalations, reducing asset downtime by 40%.

BSc (Hon) in Computing & IT – College of Computing Technology (CCT)