Senior Systems Administrator – M365 & Infrastructure

Constellation Home Builder Systems is seeking a Senior Systems Administrator / M365 & Infrastructure Administrator to join our Information Technology team in Markham, Ontario. This role will be responsible for the administration, security, governance, and strategic operation of our Microsoft 365 environment, Microsoft Entra , endpoint management systems, and collaboration technologies. The position will own technology services and responsibilities transitioning from shared corporate IT services as part of our integration with Jonas.

The successful candidate will serve as a senior technical resource responsible for identity and access management, Microsoft 365 administration, endpoint management, collaboration platforms, security governance, and infrastructure support. This individual will work closely with leadership, business stakeholders, and external vendors to ensure secure, reliable, and scalable technology services across the organization.

• Administer and maintain Microsoft Entra
• Manage user provisioning, deprovisioning, and lifecycle management
• Configure and maintain Single Sign-On (SSO) integrations
• Design and administer Conditional Access policies
• Manage Multi-Factor Authentication (MFA) technologies
• Administer external collaboration and B2B access
• Conduct identity governance reviews and access certifications
• Manage Microsoft licensing and group-based assignments
• Maintain role-based access controls and security standards

• Administer Microsoft 365 services including:
  Exchange Online Teams SharePoint Online One Drive Power Platform Power BI
• Manage retention and compliance policies
• Configure and maintain mail flow and transport rules
• Administer SPF, DKIM, and DMARC configurations
• Implement and maintain Microsoft security controls
• Support tenant governance and security best practices
• Monitor service health and platform performance
• Evaluate and implement new Microsoft 365 capabilities

• Administer Microsoft Intune
• Manage Windows Autopilot deployments
• Develop and maintain device compliance policies
• Manage application deployment and lifecycle management
• Oversee workstation configuration standards
• Manage endpoint patching and security updates
• Support remote workforce technologies

• Administer Microsoft Teams Phone Support TouchPoint and related communication systems
• Troubleshoot voice and collaboration issues
• Coordinate with telecom and technology vendors
• Manage call routing, auto attendants, and user provisioning
• Ensure reliable collaboration services across the organization

• core Windows infrastructure services
• Participate in infrastructure modernization initiatives
• Assist with cloud and hybrid infrastructure administration
• Maintain security baselines and operational standards
• Participate in security investigations and remediation efforts
• Create and maintain system documentation, procedures, and standards
• Participate in disaster recovery and business continuity planning

• 7+ years of IT infrastructure and systems administration experience
• 5+ years administering Microsoft 365 environments
• Strong experience with Microsoft Entra
• Experience implementing and supporting SSO and Conditional Access
• Experience with Exchange Online, SharePoint Online, and Teams
• Experience administering Microsoft Intune and Windows Autopilot
• Strong understanding of Microsoft licensing and tenant governance
• Experience supporting cybersecurity and compliance initiatives
• Strong troubleshooting, analytical, and problem-solving skills
• Excellent written and verbal communication skills

• Microsoft Certified:
  Identity and Access Administrator
• Microsoft Certified:
  Enterprise Administrator Expert
• Microsoft…