Senior Windows Engineer

Mizuho•New York, NY

22h•Hybrid

About The Position

Join Mizuho as a Senior Windows Engineer! The ideal candidate has deep expertise in Microsoft 365, Exchange (Online and On‑Premises), Microsoft Teams and enterprise messaging platforms. In this role, you will be responsible for technical leadership, architecture-level decision making, and delivery of complex messaging and infrastructure initiatives in a large, regulated enterprise environment.

Requirements

At least 8+ years of experience supporting enterprise Windows and Microsoft messaging platforms (financial services experience preferred).
Advanced hands-on experience with Microsoft 365 and Exchange (Online and On‑Premises) in hybrid environments.
Strong experience designing and supporting Microsoft Teams including Voice / Calling solutions
Proven leadership in delivering large-scale messaging or infrastructure projects.
Experience with Quest On Demand for migrations or hybrid integrations.
Expertise supporting Proofpoint or equivalent email security platforms.
Advanced PowerShell scripting skills.
Deep understanding of Active Directory, Windows Server, and identity integrations.
Strong working knowledge of ITIL-based service management (ServiceNow preferred).
Excellent technical judgment, communication, and stakeholder engagement skills.

Nice To Haves

Experience with VMware Horizon, Azure Virtual Desktop (AVD)

Responsibilities

Serve as a senior technical authority for Microsoft 365 and Exchange, including hybrid Exchange architectures.
Design, implement, and maintain Exchange Online and Exchange On‑Premises environments, including mail flow, transport, migrations, and coexistence.
Lead messaging and directory migration initiatives, including tooling such as Quest On Demand.
Own and integrate email security platforms, including Proofpoint, ensuring reliability, security, and compliance.
Drive end‑to‑end delivery of infrastructure and messaging projects, including upgrades, migrations, and modernization efforts.
Partner with architecture, security, and operations teams to define technical standards and roadmaps.
Author and maintain advanced PowerShell automation for administration, reporting, and operational efficiency.
Act as escalation point for complex M365, Exchange, Active Directory, and Teams issues.
Participate in vendor evaluations, solution design, and capacity planning.
Operate within ITIL-based service management frameworks and support change, incident, and problem processes.
Produce high‑quality technical documentation and provide clear stakeholder communication.
Participate in on-call rotation with senior-level responsibility and ownership.