Provides technical leadership for sustainment, refactoring, coexistence management, and modernization of legacy IMDS/IMDS-MSM components and associated enterprise workflows. This role supports analysis, decomposition, refactoring, and incremental modernization of legacy application capabilities while preserving operational stability, synchronization integrity, maintenance history continuity, and mission-critical sustainment workflows. The Senior Legacy Systems Engineer evaluates modernization candidates, identifies modernization sequencing risks, supports API modernization, validates coexistence between legacy and modernized components, and assists with migration of tightly coupled legacy workflows into modern architectures where operationally appropriate. This role works closely with the System Architect, Enterprise Integration Lead, Product Owners, DevSecOps Platform Lead, and Functional SMEs to ensure modernization activities do not disrupt maintenance scheduling, discrepancy management, disconnected operations synchronization, personnel qualification tracking, or operational reporting. The Senior Legacy Systems Engineer also supports technical debt analysis, modernization risk assessments, data integrity validation, and rollback planning during modernization execution. Requirements Must possess DoD Secret Clearance. Technical Skills · COBOL · Legacy application sustainment · Mainframe/legacy integration · Batch processing · Data synchronization · Legacy modernization techniques · API integration · SQL/Oracle Certifications Preferred: · Security+ Education · Bachelor’s degree or equivalent experience. Experience · 10+ years legacy application support. · Experience modernizing legacy enterprise applications. · Experience supporting mission-critical operational systems. Benefits • Health Care Plan (Medical, Dental & Vision) • Retirement Plan (401k) • Life Insurance (Basic, Voluntary & AD&D) • Paid Time Off (Vacation, Sick & Public Holidays) • Short Term & Long Term Disability