The "Clean Code" Reality Check: When DIY is Better Than a Library

In the modern development era, our first instinct when facing a problem is often: npm install or pip install. While the open-source ecosystem is a superpower, the "dependency-first" mindset has a hidden cost. Sometimes, the cleanest code isn't the one you imported—it's the ten lines you wrote yourself.

The Cost of the "Quick Fix"

Adding a library seems like a time-saver, but every production dependency introduces three invisible burdens:

1. The "Kitchen Sink" Problem: You need a single function to format a date, but you import a 500KB library that includes time-zone conversions, lunar calendar support, and localization for 40 languages.
2. Maintenance Debt: Every dependency is a liability. You are now responsible for tracking its security vulnerabilities (CVEs), breaking changes, and whether the maintainer decides to abandon the project.
3. The "Black Box" Bug: When a library fails, you spend hours digging through someone else's source code or issues GitHub page instead of fixing your own logic.

A Practical Example: Array Shuffling

Let's say you need to shuffle an array for a simple game UI.

The Dependency Approach

Many developers might pull in a heavy utility library like Lodash just for the _.shuffle method.

• Cost: Increases bundle size, adds a build step requirement, and introduces an external dependency.

The DIY Approach (The Fisher-Yates Shuffle)

You can solve this with a standard algorithm in plain JavaScript/TypeScript:

function shuffle(array) {
  for (let i = array.length - 1; i > 0; i--) {
    const j = Math.floor(Math.random() * (i + 1));
    [array[i], array[j]] = [array[j], array[i]];
  }
  return array;
}