What Is Nest.js and Why We Use It

Nest.js is a backend framework for building server-side applications with Node.js. It uses TypeScript by default and provides a clear structure for organizing your code.

At this point, you already know how to build a backend using Express. You can create routes, handle requests, and work with data.

However, as your application grows, the code becomes harder to manage. You start organizing files manually, repeating patterns, and mixing different parts of the logic in one place.

Nest.js solves this by introducing a structured way to build backend applications.

Instead of writing everything freely, you separate your code into clear parts:

• Controllers handle incoming requests;
• Services contain business logic;
• Modules group related functionality.

This structure makes your application easier to read, maintain, and scale.

In simple terms, Nest.js helps you move from writing working code to writing structured and maintainable backend applications.

In the next chapters, you will start building your first Nest.js application and see how this structure works in practice.