*Written by Alexandra Castelli
Hey everyone! I’m a Senior Frontend Software Engineer, and I’ve been working with TypeScript for the past 4 years. My journey with it started when I took on a personal side-project that grew more complex than I had originally anticipated. That project became the turning point where TypeScript went from “something I should try” to “something I now reach for first.”
It was during that build that I really saw how much easier—and safer—my dev life became when TypeScript entered the picture. Here’s why I chose it for that project and why you might want to consider doing the same.
TypeScript is a strongly typed superset of JavaScript that compiles to plain JavaScript. Developed by Microsoft, it extends JavaScript by adding static types, interfaces, and other powerful features that enhance development productivity and maintainability. Unlike JavaScript, which is dynamically typed, TypeScript allows developers to define data types explicitly, catching errors early in the development process.
This foundational characteristic of TypeScript is what led me to choose it for my latest project, and here’s why you should consider it too.
Since TypeScript introduces static typing, it helps catch errors at compile time rather than at runtime. By explicitly defining variable types, function parameters, and return values, TypeScript ensures fewer unexpected bugs in production and a more reliable codebase.
For example, in JavaScript, you might accidentally pass a string instead of a number, leading to runtime errors:
With TypeScript, this mistake is caught at compile time:
Because TypeScript enforces clear and structured code, it naturally improves readability. By using interfaces and type annotations, your code becomes self-documenting, making it easier for both you and other developers to understand and modify.
For example, using interfaces helps define clear object structures:
This makes the expected structure of User explicit, reducing ambiguity.
TypeScript's integration with modern IDEs like VS Code enables powerful features such as IntelliSense, auto-completion, and refactoring tools. These enhancements significantly boost developer productivity and make coding a more efficient and enjoyable experience.
For instance, when working with an object, TypeScript provides autocomplete suggestions:
This speeds up development and reduces errors.
As projects grow, JavaScript’s lack of static types can make maintaining large codebases challenging. TypeScript’s structured approach provides better organization and stability, making it the perfect choice for scalable applications.
For example, using TypeScript in a large codebase allows for safer refactoring:
Here, if a new role is added, TypeScript will ensure all necessary updates are made across the codebase.
A great advantage of TypeScript is that it is a superset of JavaScript, meaning you can introduce it gradually into an existing project. This allows teams to transition smoothly without needing to rewrite their entire codebase.
For example, you can start with simple type annotations in an existing JavaScript file:
This approach allows teams to adopt TypeScript at their own pace.
With widespread adoption, TypeScript has strong community support and is now a key part of many modern frameworks, including React, Angular, and Next.js. This ensures access to a wealth of resources and long-term sustainability.
For instance, in a React project, TypeScript enhances component safety:
This prevents common mistakes like passing the wrong prop type.
Refactoring JavaScript code can be risky, as implicit types might cause unforeseen errors. With TypeScript, refactoring becomes safer and more efficient, ensuring that changes don’t break existing functionality.
For example, renaming a function parameter is safer in TypeScript:
If the url is renamed to the endpoint, TypeScript ensures all calls to fetchData are updated accordingly.
When using AI tools like Copilot and Claude for coding assistance, providing well-defined TypeScript code leads to more accurate and relevant responses. Since TypeScript explicitly defines types, AI models can better understand the expected structure of your code, resulting in more precise debugging, refactoring suggestions, and code completion.
For example, if you ask an AI tool for help fixing a bug in JavaScript, it might struggle to infer the intended types. However, with TypeScript, the AI has clear type definitions to work with, improving its ability to diagnose issues accurately:
If you ask an AI assistant about a potential error in this function, it can quickly analyze the defined types and provide a more relevant fix.
To me, TypeScript is much more than just a typed JavaScript—it’s a powerful tool that enhances code reliability, scalability, and developer productivity. By leveraging its benefits, I’ve significantly improved my latest project’s maintainability and efficiency.
I like to consider type definitions with TypeScript to be a form of inline automated tests. By defining types explicitly, I can prevent a wide range of potential issues before they ever become a problem, making my codebase more robust and predictable.
Additionally, TypeScript improves interactions with AI development tools, leading to better responses, more accurate debugging, and improved code suggestions.
If you’re still on the fence, I highly recommend giving TypeScript a try. You may find it to be the key to a more structured and error-free development process.