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Dimitris Kyrkos
Dimitris Kyrkos

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Vibe Coding Is Great for Starting, But Not for Knowing

The new reality

You can build surprisingly far now just by prompting, iterating, copying and pasting, and letting the AI cook. A weekend project that would have taken weeks. A working prototype from a conversation. A full-stack app from someone who's never written a backend before.

And honestly? That's impressive. The barrier to building things has never been lower.

But there's a tradeoff hiding underneath all that velocity, and it doesn't show up until things go wrong.

When speed replaces understanding

The dangerous part isn't the building. It's the gap between what you've created and what you actually understand about what you've created.

When everything works, that gap is invisible. The app runs. Users are happy. Features ship fast. You feel productive.

Then something breaks. And not in an obvious way. Latency appears, and you don't know where it's coming from. Auth behaves weirdly under edge cases you never considered. State gets inconsistent across components, and you can't figure out why. Costs spike, and you have no idea which part of your system is responsible.

Now you're debugging a system you never truly understood. And the AI that built it can't reliably debug it either because it doesn't have the context of how all the pieces actually interact in production.

The complexity trap

This is the hidden tradeoff in AI-assisted development: you can generate complexity faster than you can reason about it.

Every prompt that generates a new feature adds code, dependencies, patterns, and architectural decisions to your project. When you write code manually, there's a natural speed limit that forces you to understand what you're building as you build it. You read the docs. You think about the structure. You make deliberate decisions.

With AI, that speed limit is gone. You can add an authentication system, a database layer, a caching strategy, and a payment integration in an afternoon. Each piece works. But do you understand how they interact? Do you know what happens when the cache is stale, and the auth token expires at the same time? Do you know which database queries are running on every page load?

If the answer is "not really," you haven't saved time. You've borrowed it. And the interest comes due when something breaks at 2 a.m., and you have to fix it yourself.

What this looks like in practice

I've seen this pattern play out repeatedly:

The mystery latency. An app that was fast in development suddenly slows down in production. The developer can't figure out why because they don't understand the data fetching patterns the AI set up. Turns out there are redundant API calls, N+1 query problems, and missing indexes that were invisible at low traffic.

The author's nightmare. Authentication works perfectly in happy path testing. Then a user reports they can see someone else's data. The developer doesn't understand the session management or token validation logic because the AI generated it, and they never read through it carefully.

The cost explosion. A serverless app that costs 5/monthindevelopmentsuddenlygeneratesa5/monthindevelopmentsuddenlygeneratesa500 bill. The developer doesn't know which functions are being called how often or why because the AI wired up event triggers that they never fully understood.

The impossible bug. A bug appears that only happens under specific conditions. The developer can't reproduce it, can't trace it, and can't fix it because the codebase has grown beyond their understanding. They paste the error into the AI and get suggestions that make it worse because the AI doesn't understand the full system context either.

The difference between building and understanding

Building is about getting something to work. Understanding is about knowing why it works and what happens when it doesn't.

You need both. AI gives you the first one faster than ever. But it doesn't give you the second one at all. That still requires reading the code, tracing the logic, understanding the architecture, and knowing what your dependencies actually do.

The developers who will thrive long term with AI tools aren't the ones who can prompt the fastest or generate the most code in a day. They're the ones who still take the time to understand what's been generated. Who reads through the AI's output and asks, "Why did it do it this way?" Who traces the data flow and makes sure they can explain every step. Those who treat AI output as a starting point for understanding, not a replacement for it.

Practical ways to close the gap

Read every line of AI-generated code before you commit it. Not just skim it. Actually read it. If you don't understand a line, look it up. If you can't explain what a function does, don't ship it.

Draw your architecture. If you can't sketch out how your system's components connect, how data flows, and where the boundaries are, you don't understand your system well enough. This takes 10 minutes and reveals gaps immediately.

Debug manually before asking AI. When something breaks, resist the urge to immediately paste the error into the AI. Try to trace the problem yourself first. Read the logs. Follow the code path. Even if you eventually use AI to help fix it, the debugging process teaches you about your system.

Learn the fundamentals of what you're building with. If your app uses a database, learn basic SQL and how indexes work. If it has authentication, understand tokens and sessions. If it's deployed on serverless, understand cold starts and execution limits. You don't need to be an expert, but you need enough knowledge to diagnose problems.

Review your dependencies. Know what your project depends on and roughly what each dependency does. If the AI added a library you've never heard of, spend five minutes reading its docs. That library is now part of your system, and you're responsible for it.

The long view

Vibe coding is a legitimate way to start. It lowers barriers, accelerates prototyping, and lets more people build things. That's genuinely valuable.

But starting isn't the hard part. Maintaining, debugging, scaling, and evolving what you've built is the hard part. And that requires understanding.

The builders who win long-term won't be the fastest prompters. They'll be the people who still understand what's happening underneath.

How are you balancing speed with understanding in your AI-assisted projects? Are you reading through generated code carefully or mostly trusting the output?

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