Senior Systems Engineer - Messaging & Collaboration

Senior Systems Engineer - Messaging & CollaborationNew York, NY (Hybrid, 3 days in office)Highly competitive compensation packageJoin an elite technology and research group at the forefront of global finance, where world-class engineering and quantitative research converge. This firm treats infrastructure as code and systems engineering as a competitive advantage. We are seeking a highly skilled technical leader to take ownership of the firm's critical messaging ecosystem—a complex environment where reliability is paramount, and innovation is constant.The RoleWe are seeking a deeply experienced Senior Messaging & Collaboration Engineer to serve as the firm's Subject Matter Expert (SME) on all mail-related technologies. This is not a standard administration role; it is an engineering position that requires you to bridge the gap between legacy stability and modern agility. You will own the architecture of a hybrid messaging stack that spans both Windows and Linux environments, and you will partner directly with software developers to modernize how the firm consumes and processes communication, from API migrations to Generative AI prototyping.ResponsibilitiesDesign, implement, and maintain a complex, high-availability messaging infrastructure involving Microsoft Exchange (On-Premises & Online) and Linux-based mail services (Postfix).Lead high-impact projects to modernize the messaging environment, specifically guiding the migration of applications from legacy EWS to Microsoft Graph API.Oversee the evolution of the desktop experience, managing the transition from COM-based integrations to modern Outlook JS add-ins and prototyping new AI-driven workflows.Act as the primary owner for mail security and hygiene, managing sophisticated anti-spam and threat protection gateways (Proofpoint) to protect the firm's proprietary data.Serve as a technical advisor to internal development teams, utilizing PowerShell or Python to build automation and troubleshoot complex mail routing logic.What you'll bring:7+ years of experience managing complex, enterprise-scale messaging capability.Demonstrable proficiency in managing both Microsoft Exchange (Hybrid/Online) and Linux-based mail systems (Postfix).Deep familiarity with mail-related APIs (EWS, Graph API, MAPI) and experience helping software engineers integrate with messaging platforms.Proven expertise in mail security protocols and gateways (specifically Proofpoint or similar enterprise-grade tools).A track record of troubleshooting advanced Outlook client-side issues and dissecting complex mail-flow problems in a high-pressure environment.