Why TypeScript Is Worth Your Time: A Senior Developer's Perspective

As a senior web developer who has worked on numerous projects with and without TypeScript, I've often encountered the sentiment that "types just slow you down." While it's true that TypeScript requires an initial investment of time and effort, the long-term benefits far outweigh the short-term costs. In this post, I'll explain why TypeScript is not just a trendy tool, but a fundamental shift in how we write and maintain JavaScript applications.

The Myth of Slowing Down

Let's address the ?? in the room: the idea that TypeScript slows down ?? development. While it's true that you might spend more time upfront defining types and interfaces, this investment pays off immensely in the long run. Here's why:

• Catching Errors Early: TypeScript catches many errors at compile-time that would only surface at runtime in JavaScript.
• Self-Documenting Code: Well-typed code serves as its own documentation, reducing the need for extensive comments.
• Improved IDE Support: TypeScript enables better autocomplete, refactoring tools, and inline documentation in your IDE.
• Safer Refactoring: Types make large-scale refactoring much safer and more manageable.

Code Samples: JavaScript vs. TypeScript

Here's a commonly used function to calculate the totals of some items in a ?? written in plain 'ol JS.

Now, as in most general blog posts, we are referencing a fairly simple example here, but one thing that might trip me up initially are what exactly is the shape of item? Is it .price or .cost or something else? Is it .quantity or is it .qty or something else? All of this is mental overhead that increases exponentially as the codebase grows. I'd need to log items or go check the data request or something.

Here's the same thing for TS:

First, I'll 'slow down' and export out some types from a file such as: catalog.types.ts:

In the TypeScript version:

• We've defined an Item interface, making it clear what properties an item should have.
• The function signature explicitly states it takes an array of Items and returns a number.
• If we try to pass in an array of objects missing price or quantity, TypeScript will catch this at compile-time.

Now, anywhere but anywhere that I access an Item, I will get code completion (even without AI ?? tooling ??). If I make a mistake, I will be immediately notified. No reason to wait for some dreaded undefined error to pop up in runtime!

Again, this is a small example. But as Item gets more complex, with more properties and as we write more code and logic for said Item......

Come on. Let's get nuts!

Source

Real-World Benefits

• Maintainability: As projects grow, TypeScript's benefits compound. It's much easier to understand and modify code written months or years ago when types clearly define the shape of your data and functions.
• Team Collaboration: In a team setting, TypeScript acts as a form of communication. New team members can quickly understand the codebase by looking at type definitions.
• Refactoring Confidence: When you need to make large-scale changes, TypeScript guides you through the process, showing you exactly where changes need to be made.
• Integration with Modern Tools: Many modern JavaScript tools and frameworks (like React, Vue, and Angular) have excellent TypeScript support, enhancing the developer experience.

Addressing Common Concerns

"It takes too long to set up"

Modern tools like Next.js, and Vue CLI offer TypeScript templates out of the box. Setting up TypeScript is no longer a time-consuming process. Still, it's worth it to customize and extend upon these templates. For example, here's mine.

"It's overkill for small projects"

Even in small projects, TypeScript can prevent bugs and improve code quality. The initial setup time is minimal, and the benefits are immediate.

"It's hard to learn"

While there is a learning curve, TypeScript builds on JavaScript knowledge.

And, after all, isn't anything worth doing sometimes hard to learn? Even things like getting a real estate license take time, but they can be worth doing!

We're not talking years just days, or weeks.

TypeScript isn't about slowing you down; it's about giving you the tools to move faster with confidence. The initial investment in learning and setting up TypeScript pays dividends in code quality, maintainability, and developer productivity. As our applications grow more complex, TypeScript becomes not just a nice-to-have, but a crucial tool for building robust, scalable, and maintainable web applications.

Remember, the goal isn't to write code quickly; it's to build and maintain high-quality applications efficiently. TypeScript is a powerful ally in achieving that goal.

Well, maybe for some teams that goal is only to write code quickly, but that's a whole another topic.