With IBM® i5/OS® Portable Application Solutions Environment (i5/OS PASE), you can port IBM AIX® applications to the IBM System i® platform with minimal effort.
i5/OS PASE provides an integrated runtime environment that allows you to run selected applications without the complexity of managing operating systems, such as AIX or Linux®. i5/OS PASE also provides industry-standard and de facto-standard shells and utilities that provide you with a powerful scripting environment.

i5/OS Portable Application Solutions Environment (i5/OS PASE) enables you to run many of your AIX applications on the i5/OS operating system with little or no change, and effectively expands your platform solution portfolio.
Cross-platform application development and deployment are crucial components of any effective business computing environment. Equally important are the ease of use and integration of functions that your System i model offers. As your business moves into an increasingly open computing environment, you are likely to find that achieving these often divergent goals can be difficult, time-consuming, and expensive. For instance, you might want the benefit of a familiar application that runs on and makes use of the capabilities of the AIX operating system, but you do not want the added burden of managing both the AIX and i5/OS operating systems.
This is where i5/OS PASE helps.