> I've had tremendous productivity using AI on some enormous and extremely complex projects, courtesy of modularization, separation of concerns, explicit APIs, and so on.

The problem I've had with AI systems is that they eventually realize it's possible to solve a problem by linking together two separate systems in subtle ways that result in spaghettification of good code. It takes active effort to get them to follow strict separation of concerns and modularization.

> It takes active effort to get them to follow strict separation of concerns and modularization

100% agreed. AI tools are a multiplier for experienced, conscientious developers who pay attention. Bad developers can still make bad code with any tool, and AI allows them to make more bad code quicker.

This is the gotcha here and the solution is to tell it how it should architect the software and what integration points it should use. But if you clearly define integration boundaries, the success condition, and a few other small details, it generally does a pretty good job.