8/11/2025

So You Built an App with AI… Now How Do You Fix & Maintain It?

Alright, let's be real. The first time you use an AI tool like Replit or Bolt to spin up an application from a simple text prompt, it feels like ACTUAL magic. You type "build me a to-do list app with user authentication & a clean UI," & poof, a few minutes later, you have a functional starting point. It's an incredible leap forward, no doubt. I've been there, and the rush is real. You feel like you can build anything.
But then, a week later, something breaks.
Maybe a user tries to sign up with a weird email address & the whole thing crashes. Or you try to add a new feature, & suddenly the data isn't saving correctly. The initial magic fades, & you're left with a codebase you didn't entirely write, trying to figure out why it's misbehaving. This is the new reality for a lot of builders & developers. The AI gets you 80% of the way there, but that last 20%—the debugging, the maintenance, the scaling—is a whole new ballgame.
Turns out, AI-generated code has its own special flavors of weirdness. It doesn't make mistakes in the same way a human developer does. So, if you're hitting that wall, don't worry. You're not alone. This is the guide I wish I had when I started down this road. We're going to dive deep into how to actually fix & maintain the apps you build with these amazing AI tools. We'll cover the weird new bugs they create, a solid playbook for squashing them, & the long-term habits you need to build so your app doesn't just launch, but lasts.

Part 1: Welcome to the Weird World of AI-Generated Bugs

First things first, you need to understand that the bugs you'll find in AI-generated code are... different. A fascinating study actually looked at hundreds of these bugs & categorized them into some common patterns. It's not always a simple syntax error; it's often more subtle & conceptual. If you know what to look for, you'll be way ahead of the game.
Here are the 10 most common types of bugs researchers are seeing in code from large language models:
  1. Misinterpretation: This is the big one, making up over 20% of bugs. The AI just fundamentally misunderstands your prompt. You ask for a function to sum numbers, but it gives you one that averages them. It's technically correct code, but it's not what you wanted.
  2. Missing Corner Cases: The AI is great at writing code for the "happy path." It'll work perfectly for typical inputs but completely fall apart with edge cases. For example, it might build a user profile page that works fine, but crashes if a user's name has special characters or is unexpectedly long.
  3. Hallucinated Objects: This one is wild. The AI will literally invent objects, methods, or variables that don't exist anywhere in your project. It'll write code that calls
    1 user.getProfilePic()
    when the actual method is
    1 user.getAvatarUrl()
    . It sounds plausible, but it's pure fiction.
  4. Prompt-biased Code: This is a sneaky one. The AI generates code that only works for the specific example you gave in your prompt. If you say, "translate the word 'hello' to Spanish," it might just write
    1 return "hola"
    instead of building a proper translation function.
  5. Wrong Input Type: The model uses the wrong data type for a function. For instance, it might write a function expecting a number but pass it a string, causing errors that can be hard to track down.
  6. Silly Mistakes: These are the face-palm moments. The code has redundant conditions, unnecessary conversions, or just plain goofy logic that a human would likely spot right away.
  7. Wrong Attribute: Similar to hallucinated objects, but more subtle. It uses the wrong attribute for a real object, like trying to access
    1 user.email_address
    when it should be
    1 user.email
    .
  8. Syntax Error: Yep, even the AI messes up basic syntax sometimes—missing parentheses, incorrect commas, that kind of thing. It's less common but still happens.
  9. Incomplete Generation: The AI just... stops. It cuts off mid-function or mid-sentence, leaving you with a broken piece of code.
  10. Non-Prompted Consideration: The AI adds a "feature" you never asked for. Maybe you ask for a simple data-saving function, & it decides to add its own validation step that you didn't want, which then causes the whole thing to fail for your use case.
Why does this happen? AI models don't "understand" your project in a holistic way. They lack full project context, might be trained on outdated frameworks, or just make incorrect assumptions based on vague prompts. Recognizing these patterns is the first step to becoming an effective AI-assisted debugger.

Part 2: Your Debugging Playbook: A Step-by-Step Guide

Okay, so you've got a bug. It's probably one of the weird types from the list above. Now what? Don't just start randomly changing things or hitting "regenerate" over & over. You need a process.

Step 1: Become an "Error Message Archaeologist"

Most AI platforms, especially when things go wrong on the backend, give you pretty generic error messages. But even a cryptic message is a clue. You have to dig. A great article calls this "Error Message Archaeology," & it's the perfect term.
  • Look for HTTP Status Codes: Even if they're hidden in your browser's developer tools, they tell a story. A
    1 500
    error means something broke on the server. A
    1 404
    means a missing file or a broken URL. A
    1 400
    often points to bad data being sent from a form.
  • Scan for Keywords: Look for words like "null," "undefined," "constraint," or "duplicate." These point directly to data problems.
  • Identify Field Names or API Endpoints: If the error mentions a specific field like "user_email," you know exactly where to start looking.
The goal is to find any breadcrumb that points you in the right direction instead of just staring at a blank "Something went wrong" screen.

Step 2: Use the AI to Explain Itself

Here's a pretty cool trick. If you have a chunk of AI-generated code that you don't understand, don't just try to guess what it does. Ask the AI! Most modern tools, including the AI chat in Replit, allow you to highlight code & ask questions about it.
Use prompts like:
  • "Explain this function to me like I'm a beginner."
  • "What is the purpose of this block of code? What are the expected inputs & outputs?"
  • "Walk me through the logic here, step by step."
You can't debug what you don't understand. Using the AI as a tutor for its own code is an incredibly powerful (and fast) way to get up to speed.

Step 3: The Power of the Prompt - Iterate & Refine

If the AI misunderstood you the first time, your first instinct might be to fix the code manually. But before you do that, try refining your prompt. Often, a small change in your instructions can lead to a MUCH better output.
Instead of: "Make a button that saves user data."
Try a more detailed prompt: "Create a button with the text 'Save Profile'. When clicked, it should take the data from the 'firstName' and 'lastName' input fields & save them to the 'users' database table, matching the user by the current user's ID. After a successful save, show a 'Profile Saved!' confirmation message. If there's an error, log the error to the console."
See the difference? You're providing context, specifying actions, & even dictating error handling. This massively reduces the chances of the AI making a "Misinterpretation" or "Missing Corner Cases" bug.

Step 4: Manual Fixes & Final Testing

Sometimes, you just gotta roll up your sleeves & write some code yourself. The AI might get you 95% of the way there, but you need to make that final tweak. This is where having some basic coding knowledge is a HUGE advantage. Platforms like Replit & Bolt are code-forward for a reason—they give you full access to edit the code directly.
Once you've made your fix, whether it was through a new prompt or a manual change, you MUST test it. Don't just test the happy path. Try to break it. What happens if you enter a number instead of a name? What if you leave a field blank? This is how you catch those "Missing Corner Cases" before your users do.

Part 3: Beyond the Quick Fix - Building for the Long Haul

Fixing a single bug is one thing. Maintaining an application over months or years is another. If you're not careful, an AI-generated project can become a tangled mess of unmaintainable code. To avoid this, you need to adopt some new habits.

Strategy 1: Embrace Human-AI Pair Programming

The most successful teams don't treat AI as a magic box that spits out perfect code. They treat it like a junior developer. It's incredibly fast & knows a lot, but it lacks experience, context, & wisdom.
Your role is to be the senior developer in this partnership. You guide it, you review its work, & you catch its mistakes. This mindset shift is CRITICAL. The AI is your co-pilot, not the autopilot.

Strategy 2: Test-Driven Development (TDD) is Your New Best Friend

This is a game-changer. Test-Driven Development is the practice of writing a failing test before you write the code to make it pass. In the age of AI, this is like giving your co-pilot a perfect set of instructions.
Here’s how it works:
  1. Write a simple, automated test for the feature you want. For example, a test that checks if a user can be successfully created. This test will obviously fail at first.
  2. Now, feed that test into your AI prompt. Say something like, "Here is a failing test. Please generate the code to make this test pass."
  3. The AI generates the code.
  4. You run the test again. If it passes, you know the code meets the exact requirements you defined.
This process forces clarity & gives the AI guardrails, dramatically improving the quality of the generated code.

Strategy 3: Reinvent Your Code Review Process

Code reviews are MORE important than ever with AI. But you need to look for different things. Instead of just spotting typos, your reviews should focus on:
  • Architectural Alignment: Does this new AI-generated code fit with the overall structure of our app? Or is it a weird, out-of-place module?
  • The "Why": Don't just accept code that works. Ask why the AI chose that approach. Is it efficient? Is it secure?
  • Dependencies: AI tools love to suggest adding external libraries. You need to vet these. Are they well-maintained? Are there any known security vulnerabilities?
  • Security: AI code can introduce security risks like hardcoded credentials or unprotected APIs if you're not careful.

Strategy 4: Schedule Regular Refactoring Sessions

Let's be honest, AI-generated code can be messy. It might create one giant file when it should have been three smaller ones. It often repeats code that should be put into a reusable function.
Make it a habit to schedule time for refactoring. This is where you clean things up, organize the code, & pay down "technical debt." A little bit of housekeeping every week or two can prevent your project from collapsing under its own weight.

Part 4: Essential Tools & Habits for Sustainable AI Development

Good processes are supported by good tools & habits. Here are a few non-negotiables.

Version Control is a MUST

If you're not using Git or some other version control system, start NOW. Think of it as your ultimate safety net. When the AI generates a bunch of code that breaks everything, you can instantly revert to a working version. It's a lifesaver.
A cool idea emerging is to version your prompts alongside your code. If you have a prompt that generates a key part of your application, save it! If you ever need to recreate or modify that part, you have the exact instructions you used.

Documentation: Don't Be Lazy

When you use AI, it's tempting to move so fast that you forget to document anything. BIG mistake. Your future self (or your future teammate) will be completely lost.
Keep a simple log:
  • What was the feature you were building?
  • What was the final prompt you used?
  • What manual changes did you have to make to the AI's output?
This kind of documentation is invaluable for long-term maintenance. It provides the context that is so often missing from AI projects.

Keep Your Customers in the Loop, Especially When Things Go Wrong

Here's something that gets overlooked in the rush to build: customer communication. When your app has a bug or is down for maintenance, your users get frustrated. While you & your team are busy debugging, who is handling the support emails & messages?
This is where a tool like Arsturn can be a total game-changer. Imagine you're in the middle of a frantic debugging session. Instead of being pulled away to answer the same question over & over, you could have an AI chatbot on your site doing it for you. You can train an Arsturn chatbot on your known issues, FAQs, & even your maintenance schedule. It can provide instant, helpful answers to your users 24/7, telling them you're aware of the issue & working on a fix. This keeps your users happy & lets you focus on actually solving the problem. It's about automating that crucial line of communication.

Part 5: The Future of Maintenance & Scaling Your App

The world of AI development is moving at lightning speed. Tools are getting smarter about debugging & self-healing. But what do you do as your app grows right now?
As you get more users, the demands on your time for things other than coding will skyrocket. You'll be dealing with marketing, sales questions, user onboarding, & more. This is another area where smart automation can save you.
For example, your app is now stable & you're focused on growth. But you're spending hours answering pre-sales questions from potential customers on your website. This is a perfect use case for a more advanced business solution. With Arsturn, you can build a no-code AI chatbot that's trained on all your product data, features, & pricing. It can act as a tireless sales assistant, qualifying leads, booking demos, & providing personalized experiences to every website visitor. It helps you boost conversions & build meaningful connections with your audience, all without you having to be personally involved in every single chat. It's about scaling your engagement as you scale your product.
Ultimately, you need to be strategic. You need to know when an AI-generated prototype has served its purpose & a full rewrite is necessary, & when it's a solid foundation that's worth maintaining & investing in.

Wrapping it all up

So, there you have it. Building with AI is an incredible superpower, but it's not a free pass on the hard work of software development. It just changes what the hard work looks like.
The key takeaway is this: treat AI as a powerful co-pilot, not an infallible oracle. Understand its unique quirks & failure modes. Build strong habits around testing, version control, & code reviews. And be smart about automating the other parts of your business—like customer support & engagement—so you can focus your energy on building the best possible product.
Honestly, it's a pretty exciting time to be a builder. The tools are only going to get better. By mastering the art of maintenance now, you'll be miles ahead of the curve.
Hope this was helpful! Let me know what you think.

Copyright © Arsturn 2025