> Is “you don’t really understand the code, so it’ll hurt you later” still a meaningful criticism?

That is one of the strongest valid criticisms. Even if we ignore the possibility that the code that is vibed will be buggy and insecure, the real long-term problem is not having someone who understands the system. Almost every well maintained app has one or more people who grok the whole thing, who can hear a problem described and know right where the fix will be. They'll have a mental model of the whole system and can advise on architecture changes and other refactors. They can help teach the codebase to new folks. And most importantly, when an outage happens, they are the ones who quickly get you back up and running.

The lack of those people is why legacy systems are brittle and hard to maintain, so vibe coding a complex app puts you directly into that painful legacy maintenance mode.

One thought people are starting to throw out there is, "But the AI can just re-write the whole app every time we have a bug, so we never need to know things to that level." But those people have never worked with a customer base who gets ticked off when the same bugs re-appear on every release, or when a dozen small UI changes shows up on every release.

Vibe coding might give you some working code. But working code is an astoundingly low bar to set for actually building a product that pleases a customer base.

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raw_anon_1111 20 hours ago | parent | next [-]

Understanding the system and understanding the code is different. The “system” I just mentioned was “architected” by me just like I would have done in 2018 when I first started with AWS (but with 20 years of experience with coding).

I know what every module does (well Lambda in my case but I’m trying to be more generic), I know the abstractions, I know the business case, etc.

As a team lead/architect, even with other people writing code, I don’t know every line of code does. Claude code/Codex is just a junior/mid level developer to me

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jf22 2 days ago | parent | prev [-]

The current AI tools extremely good at telling you about how an existing system works. You don't need that one super knowledgeable person anymore.

With the right MCPs or additional context you can have the tools go read PRs or the last 10 tickets that impacted the system and even go out and read cloud configuration or log files to tell you about problems.

The concept of a "bus factor" is a relic of the past.

	▲	pigon1002 2 days ago \| parent [-]
		I feel the same way. AI coding skills seem to sit somewhere between intermediate and advanced. Unless you’re working in a space where you’ve thought very deeply and developed your own solutions—those “gotcha, you didn’t know this” kinds of problems—it doesn’t really feel like AI falls short. So far, I’ve been reading through almost 100% of the code AI writes because of the traps and edge cases it can introduce. But now, it feels less like “AI code is full of pitfalls” and more like we need to focus on how to use AI properly.