[maybewhenthesun]

I helped updating ancient fortran to slightly less ancient C once. The company that depended on the ancient fortran no longer had any fortran programmers.

The resulting software upgrade was a nightmare that nearly killed that company. I shudder if someone needs to fix 20 year old AI write only code and I feel for the poor AI that has to do it. Because an AI 'intelligent' enough to do that deserves holidays and labor rights.

[geysersam]

I imagine, only slightly extrapolating current AI trends, that in 20 years most codebases can be easily modified by AI. I'd even say they are especially well suited to such tasks that typically don't require extremely abstract and complex logic, or imagination, but rather "just" a huge attention span and a lot of work.

[marginalia_nu]

Tricky bit with ancient codebases is that their only requirements, generally speaking, tend to be that they should keep working exactly like they have been since 1983, except for the bit that needs changing of course, that needs to change in a way that implements the change, but doesn't have any unintended side-effects in a system that is a fractal of undocumented interdependencies (systems that have been patched for a few decades under those types of constraints tend to become especially gnarly that way).

[demaga]

Do you mind sharing how exactly it turned out to be a disaster? What went wrong?

[maybewhenthesun]

Nothing went 'wrong' per se. they just massively underestimated how much work it would be.

Stuff was badly documented. The documentation that existed was outdated compared to the existing code. Not all executable matched the source code they were supposedly built from. It was unclear if this was because of old compiler bugs, new compiler bugs or (probably) because the source code in the backups was not the actual source code used to compile the exes and that sourcecode was long since lost to time. etc etc

I can't remember the details, it's 20 years ago.

[demaga]

Thanks for sharing. I wonder where AI-generated codebases land in terms of documentation. I bet it starts out okay or even great, but maybe degrades over time.