1. COBOL: Advanced programming, modular design, performance tuning.2. JCL: Complex job setup, PROC usage, utilities (SORT, IDCAMS).3. DB2: Advanced SQL, joins, cursors, stored procedures, bind/package management.4. VSAM: KSDS/ESDS design, IDCAMS scripting, recovery strategies.5. CICS: Transaction design, pseudo-conversational programming, resource definitions.6. Familiarity with TSO/ISPF, File-AID, Abend-AID/Xpediter, and job schedulers (CA7/Control-M).7. Strong understanding of SDLC, Agile practices, and change management.8. Excellent problem-solving, leadership, and communication skills.