M365 Senior Systems Engineer

Atlas Search; New York (NY); On-site; USD 120,000 - 160,000; Full time

Job summary

Atlas Search in New York is seeking a Senior Systems Engineer to own the Microsoft 365 platform across a multi-tenant environment. You will blend day-to-day M365 operations with leading cross-tenant migration and integration programs arising from acquisitions and divestitures.

You will manage Exchange Online, SharePoint Online, Teams, and OneDrive governance at scale, administer Entra ID and Power Platform, and apply AI-driven automation to reduce toil while ensuring security and compliance.

Qualifications

• 5+ years in Microsoft 365 / enterprise systems engineering at scale.
• Hands-on experience delivering cross-tenant migrations tied to acquisitions/divestitures.
• Strong Entra ID and Power Platform administration skills.
• Familiarity with email security standards (DMARC/SPF/DKIM) and ITSM/change management.
• Interest in applying AI and automation to reduce operational toil.

Responsibilities

• Lead M365 workstreams arising from acquisitions, mergers, and divestitures.
• Plan and execute cross-tenant migrations: mailboxes, Teams, SharePoint/OneDrive, licensing.
• Manage multi-tenant org (MTO) configuration: cross-tenant sync, shared address book, Teams Connect.
• Own Exchange Online, SharePoint Online, Teams, and OneDrive governance at enterprise scale.
• Administer Entra ID (Azure AD) and Power Platform environments, including app registrations and service principals.
• Handle eDiscovery, compliance, and email security operations.
• Triage M365 incidents and manage Windows server/virtualization infrastructure.

Skills

Microsoft 365

Entra ID

Power Platform

Multi-tenant Mgmt

Automation

Tools

Exchange Online

SharePoint Online

Teams

Job description

A major global financial services organization is looking for a Senior Systems Engineer to own their Microsoft 365 platform — a complex, multi-tenant environment reshaped continuously by M&A activity. This senior IC role blends day-to-day M365 operations with leading cross-tenant migration and integration programs whenever a deal creates one.

What you'll do:

• Lead M365 workstreams arising from acquisitions, mergers, and divestitures
• Plan and execute cross-tenant migrations: mailboxes, Teams, SharePoint/OneDrive, licensing
• Manage multi-tenant org (MTO) configuration: cross-tenant sync, shared address book, Teams Connect
• Own Exchange Online, SharePoint Online, Teams, and OneDrive governance at enterprise scale
• Administer Entra ID (Azure AD) and Power Platform environments, including app registrations and service principals
• Handle eDiscovery, compliance, and email security operations
• Triage M365 incidents and manage Windows server/virtualization infrastructure

What you bring:

• 5+ years in Microsoft 365 / enterprise systems engineering at scale
• Required: hands‑on experience delivering M&A‑driven cross‑tenant migrations — mailboxes, Teams, SharePoint, and identity consolidation tied to an actual acquisition, merger, or divestiture
• Strong MTO, Entra ID, and Power Platform administration skills
• Familiarity with email security standards (DMARC/SPF/DKIM) and formal ITSM/change management
• Genuine enthusiasm for applying AI and automation to reduce operational toil