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Use efficient file access modes (indexed vs sequential)

Minimize nested PERFORM loops

Use batch processing optimally for large data

Leverage compiler optimization flags

Limit unnecessary screen/file I/O

Protect sensitive financial data in records

Ensure proper access control in mainframe environments

Validate data formats for legacy systems

Encrypt datasets where applicable

Avoid exposing mainframe credentials in JCL

Log business events via datasets

Use DISPLAY for debug tracing

Analyze batch job reports

Profile runtime on mainframe monitors

Track dataset growth over time

Use clear section/paragraph names

Document data layouts extensively

Keep logic modular

Adopt structured programming style

Validate record formats often