A mainframe tester verifies the quality of software and applications on mainframe systems by executing tests for dependability, performance, and functionality.
They use mainframe technologies like COBOL, DB2, CICS, and JCL, performing tests such as functional, regression, system, and integration testing.
Mainframe testers identify and resolve issues, report on progress, and are skilled in both manual and automated testing, often in conjunction with agile development methodologies.