Kadmia

You've been writing JavaScript long enough to know two things:

1. You will make mistakes.

2. The same mistakes tend to resurface, wearing new hats. 🎩

That annoying 'undefined is not a function' error? Yeah, it's not going anywhere until you actually understand what caused it the first five times.

Let's get one thing straight: Leveling up in JavaScript isn't just about learning new things. It's about unlearning the bad habits and fixing the old bugs you keep repeating. Here's why going backward might be the smartest way to move forward. 🚀

🔍 Your Old Code is a Goldmine (Seriously)

Open up a project you wrote six months ago. We'll wait. Now try not to cringe. 😬

That feeling? That's progress. That's growth. And it's precisely why code review (especially your own) is one of the most underused tools in your developer workflow.

Instead of:

for (var i = 0; i < items.length; i++) {
  setTimeout(() => console.log(i), 1000);
}

You now know how to write:

for (let i = 0; i < items.length; i++) {
  setTimeout(() => console.log(i), 1000);
}

You didn't just learn how 'let' works. You learned why 'var' burned you. That "aha!" moment sticks. That's real JavaScript debugging muscle being built.

🧠 Reviewing Mistakes Builds Deep Understanding

When you hit a wall in JavaScript, it's rarely about the syntax. It's about concepts that haven't clicked yet: closures, hoisting, asynchronous behavior, scoping. You think you get them… until your code does something unexpected and confusing.

Going back to review your own bugs forces you to:

Rethink assumptions.
Spot patterns.
Strengthen problem-solving skills.

It's not sexy. It's not flashy. But it works. And the results are sticky, because you're learning through context, not just tutorials.

🧰 Make Post-Mortems Part of Your Dev Process

The best JavaScript developers don't avoid mistakes: they document them. Try this:

After every project or challenge, list the top 3 bugs that slowed you down.
Write out what caused them, how you fixed them, and how you'll avoid them next time.
Save them in a "Mistake Log" (Notion, GitHub issues, Google Doc—doesn't matter).

It's like keeping receipts… on yourself. 🧾

Over time, you'll see fewer repeated errors and more confidence when tackling new problems. That's how you become the dev who knows why things break, not just how to fix them.

⚙️ Real Learning Happens When You Struggle (and Reflect)

Passive learning feels productive: YouTube videos, docs, blog posts. But if you're not reviewing what tripped you up in real code, you're missing out on the most potent source of growth.

Every bug you debug, every error message you decode, every awkward workaround you replace with clean logic—that's where the upgrade happens.

🧩 Bonus: Reviewing Mistakes Makes You a Better Collaborator

In a team setting, knowing how to explain your past mistakes and what you've learned from them builds trust. You become someone who can:

Give better code reviews.
Mentor junior devs.
Spot issues before they hit production.

Not because you're perfect, but because you've been there, screwed that up, and took notes.

Here's the Cheat Code:

Before you dive into your next JavaScript build, take a minute to revisit what used to confuse you. Your past bugs? They've already done the hard work of showing you where you need to grow. That's not wasted time—that's your personal roadmap. 🧭

At Kadmía, we bake this kind of review into how we help devs grow: short, focused challenges that hit the exact concepts people tend to struggle the most. We're not just here to teach—we're here to make what you've already learned actually stick.

So if you're serious about leveling up, don't just move forward: loop back, get sharper, and move with intention. That's how we do it around here.