By Mainframe runs a significant share of global enterprise workloads, yet it has historically operated as a closed ecosystem, disconnected from the open source toolchains that now dominate enterprise computing. Without a neutral collaboration layer, mainframe-specific projects fragment, institutional knowledge silos, and integration with modern observability or DevOps tooling stalls. The gap between mainframe and the rest of the enterprise stack is a real engineering and organizational problem.
In this interview on TFiR, John Mertic, Director of Program Management at The Linux Foundation / Open Mainframe Project, covers the history, structure, and active projects of the Open Mainframe Project and explains how it is working to close that gap.
Guest: John Mertic, Director of Program Management at The Linux Foundation / Open Mainframe Project
Show: TFiR
Here is what every enterprise infrastructure engineer and platform team working with mainframe needs to know.
Technical Deep Dive
Q: What is the Open Mainframe Project and what problem does it solve?
John Mertic, Director of Program Management at The Linux Foundation, explains that the Open Mainframe Project is an 11-year-old initiative serving as the focal point for open source collaboration on mainframe. It began in 2015 around Linux on mainframe and IBM announcements at the time, and has since expanded to cover z/OS, COBOL, and the broader mainframe ecosystem. The core problem it solves is fragmentation: without a neutral space for collaboration, mainframe open source work would remain scattered and disconnected from enterprise tooling trends.
“The Open Mainframe Project is really the focal point for open source collaboration for mainframe.”
John Mertic, Director of Program Management, Linux Foundation
Q: How does open source on mainframe connect to the broader history of collaborative software development?
Mertic points out that open source on mainframe predates the term itself. He traces collaborative software sharing back to SHARE, an IBM user group founded in the 1950s, where engineers shared programs openly before free software or open source were defined concepts. One Open Mainframe Project project, CPT Tape, originates from that era. This history matters because it frames mainframe not as a legacy holdout resisting open source, but as a platform with deep open collaboration roots.
“We can date open source back to SHARE in the 1950s, of people collaborating in an open source way before open source was even a thing.”
John Mertic, Director of Program Management, Linux Foundation
Q: What are the key Open Mainframe Project tools that bridge mainframe and modern enterprise computing?
Mertic highlights Zowe and Galasa as two central projects. Zowe provides a modern API and CLI layer on top of z/OS, enabling developers familiar with cloud native tooling to interact with mainframe systems using standard interfaces. Galasa is an open source test automation framework built for mainframe-scale integration testing. Both projects represent the Open Mainframe Project’s goal of making mainframe fit within the larger enterprise computing world rather than remaining an isolated vertical.
“Work like Zowe and Galasa are really key parts of helping mainframe fit within the larger enterprise computing world.”
John Mertic, Director of Program Management, Linux Foundation
Q: How does the Open Mainframe Project fit within the Linux Foundation structure?
Mertic describes the Open Mainframe Project as a directed fund within the Linux Foundation, meaning it targets a specific vertical (mainframe) while benefiting from and contributing back to horizontal Linux Foundation projects. He cites OpenTelemetry as one example of a horizontal project that intersects with mainframe work. This structure lets mainframe-focused teams collaborate within a governed, neutral foundation while staying connected to broader cloud native and observability initiatives.
“This is just one of our directed funds here within the Linux Foundation, really targeting the mainframe vertical, which intersects a whole lot of other horizontals such as OpenTelemetry.”
John Mertic, Director of Program Management, Linux Foundation
Q: How rare is it for an open source project to reach 11 years of active collaboration?
Mertic notes that within the Linux Foundation, reaching a decade of active operation is uncommon. Most projects do not sustain the governance, contributor base, and ecosystem engagement needed to remain relevant for that long. The Open Mainframe Project’s longevity reflects both the stability of mainframe as a platform and the sustained enterprise demand for open source tooling around it.
“We don’t see a lot of projects get to 10 years, so it’s pretty exciting.”
John Mertic, Director of Program Management, Linux Foundation
Resources & Documentation
- Open Mainframe Project, the Linux Foundation directed fund for open source mainframe collaboration
- Zowe, open source framework providing modern CLI and API access to z/OS
- Galasa, open source integration test framework for mainframe and hybrid enterprise applications
- OpenTelemetry, vendor-neutral observability framework referenced as a horizontal Linux Foundation project intersecting with mainframe
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👇 Click to Read Full Raw Transcript
Swapnil Bhartiya: First of all, those who may not know, talk a bit about what is the Open Mainframe project all about and what role it plays not only within the Linux foundation, but also within the mainframe community.
John Mertic: Yeah, so the Open Mainframe project, it’s been around for 11 years and it’s really the focal point for the open source collaboration for Mainframe. It started around Linux on mainframe, specifically with the Linux one and several of the announcements that came out of IBM back in 2015. Over time it has grown into other areas of the mainframe zos, which is the predominant operating system cobol. And we’ve just seen a huge intake across the whole mainframe ecosystem. Open Source has always been a part of mainframe. We can date Open Source back to schare in the 1950s of people collaborating in an open source way. Before Open source was even a thing, even free software was a thing. One of our projects, CPT Tape, stretches back to that time. But really the goal here is how to collaborate, how to pull the technologies together that really help mainframe fit within the larger enterprise computing world. And that’s where we see work like Zoe and Galassa and several others there that are really key parts of that. This is just one of our directed funds here within Linux foundation, really targeting the mainframe vertical, which is nice because it intersects a whole lot of other horizontals such as opentelemetry and some other groups as well. So it’s a really, really exciting project and probably, I think one of our older projects here. From a longevity standpoint, we don’t see a lot to get to 10 years, so it’s pretty exciting.
