Most writing about the mainframe falls into one of two traps: nostalgia or hand-waving. Gulla avoids both. What he has built here is a guided walk through the z/OS stack – architecture, JES, CICS, IMS, Db2, UNIX System Services, networking, integration, security, programming languages, and the broader interface ecosystem – written by someone who actually operated the machinery for four-plus decades rather than someone narrating it from a safe distance . . .
Who it is for: technologists new to the platform, and people returning to it after time away. It is not a strategy book and does not pretend to be. It is a credible, plain-spoken field guide to the systems that still run a remarkable share of the world’s most critical transactions. For anyone who needs to understand why that is true, it is time well spent.
– Hans B. Otharsson is Chief Operating Officer at CloudFrame Inc. He leads global strategy, operational scale, and customer success for one of the industry’s most innovative mainframe modernization platforms.
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. . . Joe has almost 50 years of practical working experience in the IT field and it is abundantly clear he knows this field from top to bottom very well. More importantly, it’s also clear he is a great teacher, able to craft his lessons for optimal understanding and knowledge transfer. His assembled articles in the book are all well-organized and well presented, with appropriate teaching aids (diagrams, tables, schematics) included. I really like his eye-catching crossword-puzzle cover too!
– Arrel D. Toews is a retired professor of biochemistry and biophysics at the University of North Carolina at Chapel Hill, where he served on the faculty for more than three decades (1977–2014). Highly regarded for his dedication to students, Toews received numerous teaching awards during his tenure.
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. . . This is a good read, very thorough and detailed enough for someone to understand Mainframes.
– John McKay is Director, Global IT Services (Architecture) at TransUnion. John is a trusted technical advisor with extensive experience in IT architecture and Cloud engineering.
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. . . What I especially appreciate is that this book does not treat the mainframe as a relic of the past. Instead, Joseph shows how IBM Z continues to evolve through security, hybrid cloud integration, AI, modern development tooling, and open-source technologies. His writing makes clear why the mainframe remains central to mission-critical computing and why understanding it still matters.
I highly recommend A Mainframe Computing Reader to technologists, students, enterprise architects, and IT professionals who want to better understand the IBM mainframe ecosystem. It is an engaging, well-organized, and valuable contribution from someone who has lived the evolution of this platform and can explain it with authority.
– Felix Zalcmann – Director | Alliance Strategy & Global AI Transformation | AI Agents, Cloud, GTM | Former IBM Leader. Felix’s is responsible for the Kyndryl Global Strategic Alliance Strategy and Planning as Director Program Management.
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. . . I especially appreciated how the book reveals the continuity between older computing concepts and the foundations of today’s digital infrastructure. Gulla’s long experience in the field comes through in practical insights and memorable stories that make the material feel grounded and human, as he was deeply involved and directly hands-on with most of the systems.
– Scott Powell – LOB Executive and North America Director, Managed Cloud Services, IBM Global Services (retired).
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. . . I have read through it and I think it’s very good. Especially good if you are trying to transition to the platform or have just been made a manager of a mainframe team.
– Herbert Daly – Senior Lecturer in Computer Science at University of Hertfordshire, London, England, United Kingdom. He is a Technology Academic with a focus on innovation in through industry pathways, teaching, learning and research.
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A Mainframe Computing Reader offers a pragmatic lens on the systems that underpin modern enterprise data infrastructure. For analytics and marketing effectiveness leaders, it provides context on how data is processed at scale and the operational rigor required to sustain high-volume, mission-critical operations. That foundation remains directly relevant today, as performance reporting depends on integrating data from multiple marketing and analytics platforms through APIs and managing it efficiently at scale to support continuous optimization.
Joseph Gulla’s collection reinforces principles such as reliability and data integrity, grounded in real-world systems like transaction processing and enterprise databases. These foundational elements help to inform more durable thinking around data infrastructure and the systems that support enterprise-scale measurement.
– Sarah Collins, Senior Director of Analytics, Microsoft at Carat. Sarah is skilled in Analytics, Leadership, Data Storytelling, Brand Measurement and Paid Media Strategy
