Senior Infrastructure Engineer - Messaging

Overview

At Polsinelli, What a Law Firm Should Be is not just our tagline, it is what we live every day. We strive to create an environment where our team members are encouraged to bring their creativity and professional passions into the workplace so that they can thrive. Polsinelli, a national law firm headquartered in Kansas City, MO, is seeking a Senior Infrastructure Engineer.

Reporting to the IT Infrastructure Experience Manager, this role can be hired as remote or hybrid, provided the candidate is in a state/jurisdiction wherein we practice.

Position Overview

This senior role leads the day-to-day administration and engineering of our Exchange Servers and Exchange Online environment. The ideal candidate pairs strong attention to detail with deep email infrastructure knowledge and advanced Power Shell and Microsoft Graph automation skills. The engineer plays a critical role in designing, implementing, and supporting a reliable, secure, and scalable Microsoft 365 messaging environment with a focus on Exchange Online, ensuring availability, security, compliance, and performance in a hybrid, multi-office law firm environment.

The role also serves as a technical lead for Microsoft 365 messaging services, including Microsoft Purview, Mimecast (or similar email security platforms), Microsoft Teams, centralized email signature tools such as Exclaimer, and Microsoft 365 tenant settings that affect mail flow, hygiene, retention, and compliance, in close partnership with Endpoint Management and Identity teams for Intune, Conditional Access, and related identity controls.

• Serve as the technical lead and key owner for the firm’s Exchange Online, Exchange Server, and related Microsoft 365 messaging services, ensuring availability, security, compliance, and performance in a hybrid law firm environment.
• Help drive the maintenance, design, development, support, and security of the firm’s messaging services, treating email and calendaring as critical business applications.
• Provide 24x7 support for critical production messaging systems as part of an on-call rotation.
• Lead or play a key role in migration efforts from Exchange Server Subscription Edition to Exchange Online, and contribute to planning for future tenant-to-tenant Exchange Online/Microsoft 365 migrations to support acquisitions and integrations.
• Manage and monitor Microsoft 365 tenant components that affect messaging, including mail flow, message hygiene, retention, compliance, DKIM, DMARC, SPF, and Mimecast (or similar products).
• Collaborate with Endpoint Management and Identity teams on Intune, Conditional Access, MDM/MAM, and identity controls (Entra , Active Directory, Okta) to ensure secure, low-friction access to messaging services.
• Provide advanced administration, technical support, and troubleshooting for complex issues involving Microsoft Exchange Online and Exchange Server in a hybrid environment, acting as a Tier 3 escalation point.
• Configure and support Microsoft Purview features related to messaging and collaboration, including data loss prevention, retention, and eDiscovery, in partnership with Security and Compliance teams.
• Design, implement, and maintain automation and reporting for messaging operations using Power Shell and Microsoft Graph to reduce manual work and improve consistency at scale.
• Develop and maintain documentation, runbooks, knowledge articles, and monitoring/alerting for messaging and collaboration services.
• Implement capacity planning and proactive remediation to address issues before they impact users, and provide input to IT leadership on technology improvements, standards, and roadmap for messaging and Microsoft 365 collaboration.
• Partner with Help Desk, Deskside, and other support teams to resolve escalated messaging tickets, mentor staff on common patterns, drive root cause analysis, and reduce recurring issues.
• Experience with centralized email signature management platforms (such as Exclaimer) or similar products for firmwide email signatures and branding is a strong plus.
• Other duties as assigned.

Employees approved for flexible work arrangements are expected to be available and maintain a…