IBM mainframe technology has been providing power and reliability for mission-critical transaction processing for decades, and remains a foundation for IT systems in many industries. In a fast-paced digital world however, mainframe application development is challenged to keep pace with accelerated release cadences of open systems in the IT portfolio. Testing resources are limited and expensive, slowing native development or modernization projects. Application teams are forced to either reduce test coverage and compromise quality to maintain schedule, or delay delivery of critical code changes.