Senior Microsoft 365 Engineer

Optiver's Global Enterprise Clients team owns the global Microsoft 365 platform — collaboration, messaging, identity, and mobile access — that our entire worldwide workforce runs on every day. It's treated as critical production infrastructure, not a back-office system. You'll join an established, distributed group of senior Microsoft 365 engineers spread across our global offices, operating a single global platform, in a hands-on role with real architectural influence: engineers here design solutions, validate them with peers, and implement them directly.

Observability, continuous capability uplift, CI-driven change, and self-healing automation are central to how we keep this platform reliable at scale.

• Set direction and design standards for our global Microsoft 365 platform across collaboration, messaging, identity, and device access
• Lead arcitectural decisions end-to-end — design, peer validation, implementation — driving change from inception through global rollout and adoption, with full ownership of global deliverables
• Drive systemic simplification, reducing legacy patterns, hybrid complexity, and accidental architecture
• Define and operate our collaboration and content platforms, including information architecture, governance, permissions, and lifecycle management
• Own enterprise messaging architecture, including global mail flow, routing, hybrid integration, and coexistence
• Architect identity and access foundations, covering authentication models, access control, lifecycle management, and hybrid integration
• Define and own mobile access architecture for iOS and Android
• Architect the Azure foundations that support Microsoft 365, identity, automation, monitoring, and remediation
• Treat observability as non-negotiable — design deep monitoring, alerting, and telemetry, using tooling that surfaces systemic risk and informs decisions
• Own BAU operations for the platform, including incidents, degradations, change execution, and continuous improvement
• Design, implement, and operate self-healing automation that closes the loop between detection, remediation, and prevention
• Build and maintain production-grade automation using industry-standard tooling, including AI-assisted development where it accelerates delivery without reducing ownership

You'll join a culture of collaboration and excellence, surrounded by curious thinkers and creative problem-solvers. Motivated by a passion for continuous improvement, you'll thrive in a supportive, high-performing environment alongside talented colleagues, collectively tackling some of the toughest challenges in the financial markets.

In addition, you'll receive:

• The opportunity to work alongside best-in-class professionals from over 40 different countries
• Highly competitive compensation package, including a global profit-sharing pool and performance-based bonus structure
• 401(k) match up to 50%
• Comprehensive health, mental, dental, vision, disability, and life coverage
• 25 paid vacation days alongside market holidays
• Extensive office perks, including breakfast, lunch and snacks, regular social events, clubs, sporting leagues and more

• 7+ years' experience as a senior Microsoft 365 engineer or architect, owning and operating mid-to-large enterprise platforms
• Deep hands-on expertise in SharePoint Online platform engineering and Exchange Online mail flow, including hybrid scenarios
• Strong command of identity and access architecture, including Entra  / Azure AD and Entra  (Conditional Access, tenant restrictions, B2B, RBAC, enterprise apps, service principals, app proxy)
• Proven track record simplifying complex hybrid environments
• Strong Power Shell engineering skills and comfort with Microsoft Graph, Azure CLI, Terraform, and Git Hub-based Infrastructure-as-Code workflows
• Highly proficient with Log Analytics and KQL
• Comfortable designing and operating Azure resources — policies, subscriptions, workbooks, storage accounts, VNETs, Traffic Manager
• Experience defining and owning MDM/Intune policy and configuration for iOS and Android, across both BYOD and corporate-managed settings
• Comfortable debating architecture with senior peers and backing decisions…