One of the major trends in computing in the last decade has been open source. It’s a fundamental shift that has changed how programmers and engineers interact with systems and build the tools that power the world. In order to remain at the forefront of enterprise computing, it is critical for mainframes to embrace open-source frameworks and tooling to broaden the utility of these systems to solve critical business and technical problems. Zowe is playing a key role in driving this adoption, as are open source tools that allow users to program in any language that they want, such as Python. But the most important driver of the open-source mainframe revolution is for all of us to start building open source applications and interfaces on mainframes.