The IRS was among the first institutions to adopt computers systems to perform business functions. Deployed 60 years ago, the IRS’s Individual Master File (IMF) system is one of the oldest computer systems still in operation in the world and the oldest in the Federal government. Like many IRS systems, the IMF executes on a mainframe. There are few governments, corporations or other federal agencies who utilize the mainframe platform as much as the IRS.


Over the past 10 years, Congress has reduced the IRS budget by 20%, while its responsibilities have increased substantially. Such budget constraints have forced the IRS to stretch the capabilities of its legacy platforms. With such a substantial investment in the mainframe, the IRS needed a way to make best use of the technology in the present and future. Unfortunately, the IRS had moved away from building new systems on the mainframe, and instead are building them on Windows and Linux platforms.

The Solution

Needing to enhance the viability of the mainframe, IBM introduced Linux on IBM Z, a Linux operating system that can execute on an IBM mainframe. Even though the technology was available for some time, the IRS had little experience with it. IRS engineering needed expert help to develop a solution to migrate systems to the mainframe Linux environment. The IRS turned to Northrop Grumman for the expertise, who turned to STP. Fortunately, STP was up to the challenge. STP’s Sr. Linux Engineer, with over 10 years of experience building Linux based solutions on the mainframe provided over 5,000 hours of expertise to the IRS’s efforts to migrate applications and systems to a mainframe Linux environment.