Core Responsibilities Application Development and Engineering Design, write, test, and implement complex, highly secure batch and online programs utilizing enterprise COBOL within IBM zOS environments. Transaction Processing CICS Architect and optimize online CICS applications to ensure ultra-low latency, optimal screen data layouts, high-volume throughput, and robust error-handling protocols. Database Management DB2 Design efficient relational tables, write high-performance embedded SQL statements, and optimize DB2 store procedures, indexes, and queries to eliminate processing bottlenecks. Batch Architecture and JCL Manage, write, and optimize complex JCL Job Control Language streams, utilities IEBGENER, IDCAMS, SORT, and automated batch scheduling systems. Performance Tuning and Debugging Perform advanced root-cause analysis, system tracing, and performance tuning using tools like Dump Analysis, Xpediter, InterTest, or File-AID to maintain high availability. Systems Integration and API Enablement Partner with Cloud and Integration Architects to expose core mainframe data and transactional logic to modern RESTful APIs via zOS Connect or MQ Series. Technical Stewardship Define and enforce coding standards, lead rigorous code reviews, and maintain comprehensive documentation for legacy architectures. Required Technical Stack and Experience Experience 8 plus years of professional experience in IBM Mainframe software engineering. Proven track record in high-volume, transactional environments e.g., Financial Services, Healthcare, Logistics, or Insurance. Skill Matrix Domain Required Tooling and Concepts Languages Enterprise COBOL, JCL, Embedded SQL, Assembler/EZTrieve is a plus Online Processing CICS BMS Maps, TS/TD Queues, Program Control, Intercommunication Data Management DB2 Relational design, .