Someone asked me last week if legacy code will disappear now that AI writes so much of our software. My first answer was a quick "no." Then I looked into it, and the real answer turned out to be more interesting than a simple no.
The story we tell ourselves
The pitch for AI coding tools always sounds the same. Feed the model your old codebase, and it will read the messy parts, explain the parts nobody remembers, and modernize what needs to change. In theory, legacy code stops being scary. It becomes just another input for a model with a big context window.
There is some truth here. In March 2026, Anthropic launched the Claude Partner Network with a $100M commitment, and legacy code modernization was one of the main use cases they pointed to. Cleveroad, a company that works on these migrations, explains that AI-assisted modernization reads existing code and translates it step by step, instead of throwing it away and starting over. A full rewrite is risky. You lose business rules that got buried in the code over the years, rules nobody wrote down anywhere else. AI tools are good at pulling that hidden logic out before anything gets touched.
So on the enterprise side, there is a real market forming around this. IBM i shops, old RPG systems, COBOL wrappers, all of it. Companies like ARCAD, Fresche, and Profound Logic are building tools and services around exactly this problem. If legacy code was disappearing, nobody would be selling shovels for it.
