That would be possible if you had just the spec, but after sometime most of the code will not have been generated through the original spec, but through lots of back and forth for adding features and big fixing. No way to run all that again.

Not that old big non-AI software doesn't have similar maintainability issues (I keep posting this example, but I don't actually want to callthat company out specifically, the problem is widespread: https://news.ycombinator.com/item?id=18442941).

That's why I'm reluctant to complain about the AI code issues too much. The problem of how software is written, on the higher level, the teams, the decisions, the rotating programmers, may be bigger than that of any particular technology or person actually writing the code.

I remember a company where I looked at a contractor job, they wanted me to fix a lot of code they had received from their Eastern European programmers. They complained about them a lot in our meeting. However, after hearing them out I was convinced the problem was not the people generating the code, but the ones above them who failed to provide them with accurate specs and clear guidance, and got surprised at the very end that it did not work as expected.

Similar with AI. It may be hard to disentangle what is project management, what is actually the fault of the AI. I found that you can live with pockets of suboptimal but mostly working code well enough, even adding features and fixing bugs easily, if the overall architecture is solid, and components are well isolated.

That is why I don't worry too much about the complaints here about bad error checks and other small stuff. Even if it is bad, you will have lots of such issues in typical large corporate projects, even with competent people. That's because programmers keep changing, management focuses on features over anything else (usually customers, internal or external, don't pay for code reorg, only for new features). The layers above the low level code are more important in deciding if the project is and remains viable.

From what the commenters say, it seems to me the problem starts much higher than the Claude code, so it is hard to say how much at fault AI generated code actually is IMHO. Whether you have inexperienced juniors or an AI producing code, you need solid project lead and architecture layers above the lines of code first of all.

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