Izzi Reimagines Mainframe Debugging with VS Code Integration

MINNEAPOLIS, MN – February 02, 2026 – In a move that bridges decades of computing history with modern development practices, Izzi Software has announced the upcoming release of its Z/XDC debugging suite for Visual Studio Code. The initiative aims to transplant the powerful, four-decade-old mainframe debugging engine from ColeSoft, which Izzi owns, into the world's most popular code editor. This strategic integration, accompanied by a company-wide rebranding, represents a significant effort to address the persistent skills gap in mainframe computing and redefine the developer experience for a new generation.

The announcement signals more than just a product update; it reflects a broader industry trend of integrating stalwart enterprise systems with contemporary, agile workflows. As mainframes continue to process the bulk of the world's financial transactions and mission-critical data, the challenge of maintaining and evolving these systems has become paramount.

The Mainframe Conundrum: A Modern Solution to a Generational Gap

The mainframe market is not fading; it's growing. Projections show the global market size expanding from $2.7 billion in 2024 to over $4.7 billion by 2033. These powerful machines remain the backbone for industries like banking, insurance, and logistics due to their unmatched reliability and security. However, the human element that powers them is facing a critical juncture. The average mainframe specialist is over 50, and a wave of retirements is creating a severe skills gap. One industry report noted that 56% of enterprises struggle to find mainframe skills in new hires, and it can take up to two years to get a new developer proficient on the platform.

Izzi Software's launch of Z/XDC for Visual Studio Code directly confronts this challenge. By embedding its debugging tools within the VS Code environment, the company is lowering the barrier to entry for millions of developers who are already fluent in the IDE but have never touched a traditional mainframe interface, often referred to as a "green screen."

“For more than 40 years, ColeSoft has produced superior debugging products for software engineers and support staff on IBM mainframes,” said Jennifer Nelson, CEO of Izzi Software, in the company's press release. “This solution is pervasive, so releasing a modern UI for the mainframe community represents an important step in evolving this solution for the future and making it more accessible for new users while retaining its expansive features for veteran developers who prefer ISPF. A new generation of software developers can now leverage our powerful suite of debugging tools using a modern, familiar interface, eliminating the need to invoke a terminal emulator.”

This approach aligns with broader modernization efforts, such as the open-source Zowe framework, which also provides a VS Code extension for mainframe interaction. The goal is to make mainframe development less of an isolated discipline and more of an integrated part of a modern, multi-platform DevOps pipeline.

A New Era for Developers: From Terminal to Interactive IDE

For developers, the practical impact of this shift is profound. Traditional mainframe debugging often involves navigating complex, character-based interfaces like ISPF. While powerful in the hands of a seasoned expert, these environments can be unintuitive and cumbersome for newcomers, steepening the learning curve and slowing down productivity.

The Z/XDC plugin for VS Code promises a paradigm shift. It allows for interactive, real-time debugging directly within a familiar graphical interface. This modernizes the workflow by enabling features that developers on other platforms take for granted, such as intuitive breakpoints, variable inspection, and seamless navigation through code. The result is a more engaging and efficient development cycle.

This modernization is crucial for attracting talent. Industry experts agree that the lack of modern tooling is a significant deterrent for young developers considering a career in mainframe technology. By providing a development experience on par with web and mobile development, companies can better market mainframe careers as strategic, secure, and technologically current. This can dramatically streamline the onboarding process, allowing new hires to become productive contributors much faster.

The Business Blueprint: Big Band's Bet on Niche Software

Behind this technological refresh lies a calculated business strategy orchestrated by Izzi Software's parent company, Big Band Software. Founded in 2023 and backed by private equity, Big Band operates on a unique "founder-first, people-first" model. It targets established, profitable, and often founder-led B2B SaaS companies with annual recurring revenues between $2 million and $10 million.

Izzi Software, launched in late 2024 and led by CEO Jennifer Nelson, a 15-year veteran of the mainframe space, acts as Big Band's specialized arm for the IBM z (mainframe) and IBM Power systems industries. Its mission is to acquire and cultivate businesses with mission-critical software, preserving their institutional knowledge while investing in growth and modernization.

ColeSoft, acquired in late 2024, was Izzi's inaugural purchase. Founded by Dave Cole in the 1980s, ColeSoft built a sterling reputation over four decades for the reliability and depth of its Z/XDC debugging suite. Rather than absorbing and dismantling the company, Izzi's strategy is to leverage ColeSoft's proven technology and deep market penetration as a foundation for future growth. The VS Code integration is the first major product of this strategy, combining a trusted legacy engine with a modern user experience to expand its market reach.

This approach avoids the common "strip and flip" model of private equity, focusing instead on long-term value creation by evolving niche products for a changing technological landscape. By acquiring other complementary companies, such as its 2025 purchase of CNX for IBM Power systems, Izzi is building a portfolio designed to offer comprehensive solutions for enterprise infrastructure.

By modernizing the user-facing aspect of a deeply embedded and trusted tool, Izzi Software is not only ensuring the product's relevance for years to come but also providing a vital service to the entire mainframe ecosystem. This dual focus on technological innovation and strategic acquisition provides a powerful blueprint for sustaining the critical enterprise systems that underpin the global economy.