Available for Infrastructure Projects · Lagos, Nigeria

I keep enterprises
running & migrating
without breaking a sweat.

Senior Infrastructure Engineer with 7+ years delivering zero-downtime migrations, hybrid cloud operations, and enterprise security frameworks for banks, fintechs, and corporates across Africa and beyond.

See My Work ↓ Download CV ↗
🏦 GTBank Infrastructure Lead
☁️ Azure Hybrid Cloud
⚡ 500+ Mailbox Migrations
🛡️ MS-102 · SC-300 · AZ-800
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0 Years of Experience
0 + Mailboxes Migrated
0 + Users Migrated (Emple Group)
0 Microsoft Certifications
Samuel Omoyin
7+ Yrs Exp
About Me

Infrastructure is personal to me.

I'm Samuel Omoyin — a Senior Infrastructure & Modern Workplace Engineer based in Lagos, Nigeria. For over 7 years, I've been the person companies call when they need their Microsoft 365, Azure, and Active Directory environments to work flawlessly — especially when something big needs to change.

I've run the infrastructure show at GTBank Nigeria, led a zero-downtime Exchange 2016→2019 upgrade for 500+ mailboxes, and delivered complex cross-forest AD migrations for organisations going through transformation. What I love most? Turning a complicated migration that feels impossible into a smooth cutover that nobody notices happened.

Exchange Server Microsoft Azure Active Directory PowerShell DLP & Compliance Hybrid Cloud Zero-Downtime Migrations Microsoft Entra ID
Technical Skills

Built for the enterprise stack.

🖥️
Infrastructure & Servers
Exchange Server 2016/2019 Windows Server IIS Domain Controllers Azure VMs Azure Blob & File Storage
☁️
Cloud & Hybrid
Microsoft Azure Hybrid Config Wizard Entra Connect (AD Connect) Hybrid Cloud Ops Microsoft 365 Admin
🔐
Identity & Access
Microsoft Entra ID AD Domain Services MFA & SSPR Conditional Access RBAC SSO / SAML / OAuth 2.0
⚙️
Automation & Scripting
PowerShell Microsoft Graph API Python Lifecycle Automation Bulk Operations
🚚
Migration Tools
Quest Migration Manager ADMT Password Export Server SharePoint Migration Mgr Exchange Online Migration
🛡️
Security & Compliance
Defender for Office 365 DLP Policies Insider Risk Management Endpoint Security Audit Logging Patch Management
Experience

Where I've made impact.

Ha-Shem Limited Aug 2024 – Present
Upwork (Freelance) Mar 2024 – Jul 2024
Teknowledge (TekExperts) Aug 2022 – Jan 2024
Cardinal Security Services Apr 2022 – Aug 2022
Modern Workplace & Infrastructure Engineer
Ha-Shem Limited · Lagos, Nigeria
August 2024 – Present
  • Ongoing Level 2 infrastructure lead for GTBank Nigeria, managing Exchange Server, Domain Controllers, and M365 workloads in a mission-critical banking environment with strict SLA requirements.
  • Architected and executed a full Tenant-to-Tenant and AD migration for ZoneNetwork from Qore.inc, using ADMT and Quest Migration Manager for seamless identity and data transition.
  • Led Emple Group's 300+ user migration — Exchange Online, SharePoint, OneDrive, Teams, and M365 Groups — using Quest tooling with zero service disruption.
  • Delivered a zero-downtime Exchange 2016→2019 upgrade for 500+ mailboxes, coordinating backups, scheduling, and post-migration verification end-to-end.
  • Executed a Cross-Forest AD migration of 170+ users, 170+ computers, 100+ GPOs with PowerShell automation preserving full identity and policy integrity.
  • Designed and deployed DLP and Insider Risk Management policies for multiple enterprise clients, ensuring data sovereignty compliance.
  • Built PowerShell automation scripts eliminating manual overhead across deployment and lifecycle management processes.
Microsoft 365 Business Advisor
Upwork (Freelance)
March 2024 – July 2024
  • Delivered targeted M365 recommendations to enhance productivity and collaboration for global clients.
  • Advised on subscription plans, resulting in 15+ successful plan upgrades.
  • Enabled 40% of engaged customers to transition from grace periods to perpetual licenses.
  • Facilitated new subscriptions and upgrades with step-by-step guidance and proactive troubleshooting.
L2 Technical Support Engineer – M365 Enterprise
Teknowledge (formerly TekExperts) · Lagos, Nigeria
August 2022 – January 2024
  • Delivered Level 2 support for global enterprise clients across the US, Canada, and Europe, resolving 100+ high-complexity incidents across Windows and macOS.
  • Managed hybrid auth infrastructure, synchronising on-prem identities with Microsoft Entra ID via Entra Connect.
  • Automated user lifecycle management with PowerShell and Microsoft Graph API, reducing provisioning workloads significantly.
  • Configured enterprise SSO integrations (SAML/OAuth 2.0) for AWS, Salesforce, and other enterprise platforms.
  • Conducted deep-dive threat investigations using Defender for Office 365 and Secure Score analytics, contributing to infrastructure hardening recommendations.
  • Monitored infrastructure alerts proactively, resolving service disruptions ahead of SLA thresholds.
IT Support Specialist
Cardinal Security Services Limited · Lagos, Nigeria
April 2022 – August 2022
  • Managed internal hardware and software infrastructure, diagnosing and resolving system issues to maintain operational continuity.
  • Conducted technical training sessions for staff, improving IT proficiency and reducing support ticket volumes.
  • Identified and implemented process improvements to simplify operations and increase efficiency.
Case Studies

Real projects, real numbers.

Microsoft Infrastructure Support GTBank · Nigeria

GTBank — Ongoing Enterprise Infrastructure Support

Serving as the ongoing infrastructure anchor for one of Nigeria's largest financial institutions. Day-to-day ownership of Exchange Servers, Domain Controllers, and Microsoft 365 workloads in a high-availability environment where downtime is simply not an option. Stringent SLA adherence with proactive monitoring, incident resolution, and compliance management.

Exchange Server Domain Controllers M365 SLA Management Windows Server
99.9%Uptime maintained
Bank-gradeSLA compliance
L2Escalation point
M365 Tenant-to-Tenant Migration Emple Group

300+ User Tenant-to-Tenant Migration

Led the full M365 migration for Emple Group — Exchange Online, SharePoint, OneDrive, Teams, and M365 Groups — delivered on schedule with zero service disruption using Quest tooling.

300+Users migrated
0Downtime events
5Workloads moved
Quest Migration Mgr Exchange Online SharePoint Teams
Exchange Server Upgrade Mutual Assurance Benefit (MBA)

Zero-Downtime Exchange 2016 → 2019 Upgrade

Orchestrated a meticulous staged upgrade from Exchange Server 2016 to 2019 for 500+ mailboxes. Pre-migration planning, backup validation, cutover scheduling, and rollback procedures executed flawlessly.

500+Mailboxes upgraded
ZeroDowntime
Exchange 2019 Windows Server PowerShell
Cross-Forest AD Migration Zone Payment Network

Cross-Forest AD Migration — 170+ Users & GPOs

Executed a complex cross-forest AD migration preserving SID history, group memberships, and all 100+ GPOs. PowerShell automation ensured identity integrity throughout.

170+Users migrated
100+GPOs preserved
170+Computers moved
ADMT PowerShell PES Group Policy
Automation PowerShell Tool

Windows Server Health Check Automation Framework

Built a PowerShell + Microsoft Graph API automation that continuously audits Windows Server and M365 health — CPU, memory, disk, services, event logs, MFA coverage, licence consumption, Conditional Access status, and sync errors. Outputs structured HTML/CSV reports for proactive incident resolution.

ProactiveIncident resolution
AutomatedCompliance auditing
PowerShell Graph API HTML Reports M365 Monitoring
Certifications

Microsoft-certified expertise.

M
Microsoft 365 Administrator Expert
MS-102
M
Identity & Access Administrator Associate
SC-300
M
Administering Windows Server Hybrid Core Infrastructure
AZ-800
M
Security, Compliance & Identity Fundamentals
SC-900
M
Microsoft 365 Certified: Fundamentals
MS-900
🎯
Always Learning
Next: AZ-104 in progress
Get In Touch

Let's build something solid.

Whether you're planning a migration, rebuilding your M365 environment, or need an infrastructure engineer who takes ownership — I'd love to hear about your project.

📞 +234 813 296 7555  |  +234 818 821 3688