Leidos Digital Modernization Sector is seeking an experienced Senior Cloud Engineer Architect (AWS) to support large-scale migration and operations on a large, high-profile DOD contract. The I3TS program provides enterprise-wide IT support to enable DTRA's Information Management & Technology Directorate (ITD) to consolidate, modernize, and continuously innovate the delivery of IT services and mission capabilities to DTRA's internal and external mission partners operating in CONUS and OCONUS locations. The Senior Cloud Engineer Architect (AWS) supports design of a new, modernized updated and upgraded capabilities for DTRA. This role will be responsible for tech requirement definition, feasibility studies, pilot projects and implementations plans, as well as diagnosing and troubleshooting outages, monitoring networks, infrastructure and systems, and proving proactive mitigation strategies. This role is part of a highly skilled technical team responsible for designing and deploying secure, scalable, and compliant hybrid- and multi-cloud architectures that enable mission success across complex defense environments. The ideal candidate will have deep expertise in AWS cloud architecture, identity and access management (IAM), AWS Identity Center, and multi-cloud interoperability, with a proven ability to operate in DoD-accredited cloud environments. This position requires architectural vision, and hands-on technical experience with both AWS and other major cloud providers (e.g., Azure).