Mainframe Unix System Services

Today’s mainframe computers - and I’m referring specifically to IBM zSeries and corresponding z/OS - are an incredibly versatile resource. Many people already know that mainframes can run Linux in its own VM, side-by-side with z/OS, and this is a great option for running Linux-native applications on the mainframe. But most mainframe shops today have deep roots in batch z/OS and CICS. How do you make use of new technologies and skill sets (including new hires with little or no experience with Cobol), without totally rewriting your applications?