AI Is Changing the Business Case for PICK MultiValue Modernization
By Mike Wright, CTO, Zumasys
For most of my career, I’ve argued against large-scale legacy system rewrites. Not because I resist change. Not because I think legacy technology is better. And not because legacy systems are easy to live with. I was opposed because, in many cases, businesses were rarely equipped to commit completely to a full rewrite. Whether the constraint was time, resources or money, something would be left on the table and the business would be left to suffer.
Legacy systems often contain years, if not decades, of hard-earned business knowledge. They support critical operations, handle important workflows, and reflect countless decisions made over time. While the technology may be outdated, the business logic inside these systems is often extremely valuable. All of your legacy code represents the collective brain of your organization.
For a long time, the practical strategy was to modernize around the legacy system rather than replace it outright. Build better user experiences. Improve integrations. Add reporting. Extend the life of the system without taking on the cost, disruption, and risk of a full replacement. A rewrite could take years. It could cost far more than expected. It could introduce new operational risks. And even after all that investment, the new system might still fail to fully capture the behavior of the old one. For many organizations, the safer and smarter decision was to protect what worked and modernize gradually. I still believe that is true in many cases, but the conversation is no longer so black and white.
AI assisted development has changed the economics of modernization. It does not remove the need for strong leadership, experienced teams, sound architecture, or careful planning. It does not make legacy modernization easy. But it does reduce the cost and effort of some of the hardest parts of the work. The question was never whether or not languages like PICK BASIC could be completely translated to languages like C#, Java, Go or Rust. The question was whether organizations would commit enough time, resources and money towards completing that translation while ensuring nothing was left behind. That’s where AI has flipped the script.
AI can help teams understand older systems faster. It can explain existing code, identify business rules, generate documentation, create test scenarios, and help translate functionality into newer platforms. In practical terms, AI can reduce the time required to analyze and recreate important system behavior. That matters because many modernization decisions have historically been made before the full business case was ever explored. Leaders often rejected deeper modernization not because it lacked value, but because the cost and uncertainty were too high.
With tools like GitHub Copilot, teams can move faster in systems that once required significant manual effort to understand and change. Work that previously felt too expensive or too risky may now be worth evaluating more seriously. This does not mean every legacy system should be rewritten. Here at Zumasys, GitHub Copilot is writing more OpenQM BASIC than C#, Vue.js and TypeScript. That is powerful because it allows us to strategically decide when and where to move code without having to fear making sacrifices due to budget or time constraints.
The goal was never to preserve legacy technology for its own sake. The goal was to preserve business value while improving speed, flexibility, usability, and long-term maintainability. If AI can help organizations move valuable business logic into modern platforms faster, with more confidence and lower cost, then leaders should be willing to revisit strategies that once seemed settled.
Legacy systems still deserve respect. They often contain the institutional knowledge that keeps a business running. But respect does not have to mean permanence. For years, the safest advice was to modernize the edges and leave the core alone.
Now, in some cases, the better business decision may be to modernize the core too.
