Working closely with program leadership, system owners, developers, ISSMs/ISSOs, enterprise architects, and cybersecurity operations teams, the ISSEs will align enterprise and edge architectures with federal security requirements-including NIST 800‑53, RMF, ICD 503, and DAAPM-and ensure secure, real‑time system operation throughout MAJESTIC's mission landscape. The Enterprise ISSE will design, develop, implement, and validate security architectures for MAJESTIC's core systems and enterprise environments, ensuring security controls are integrated throughout the full engineering lifecycle-from requirements and high‑level architecture through deployment, sustainment, modernization, and ATO maintenance.