What is Bundling and Code-Splitting?
Tags: webdev, programming, codenewbie, frontend
Published: 2023-10-15 08:40:02

Greetings fellow web developers! Have you been struggling with slow load times and sluggish application responsiveness? Fear not, the answer to your problems lies within the power of web bundlers. But what exactly are these mysterious frameworks, and how can you harness their potential to enhance your web applications?

Let's dive into the world of bundling and learn how to optimize your codebase like a pro!

## Understanding the Need for Bundling

Browsing the web can be a frustrating experience if you're stuck waiting for a slow-loading website. Have you ever found yourself tapping your foot impatiently, waiting for a page to load? Well, that's where bundling comes in to save the day!

When a browser tries to load a web application that is made up of multiple modules, sub-modules, third-party dependencies and other components, it needs to request each of these files individually. And, as you can imagine, this process can be quite slow and cumbersome. This can lead to longer load times, decreased application responsiveness, and a generally frustrating user experience.

But with bundling, we can turn this problem around!

## The Secret to Faster Load Times: Bundling

Bundling is a technique in web development that involves combining multiple files and modules into a single, optimized file. This process involves a compiler that resolves module dependencies and merges them into a single bundle for the browser to use. By bundling, you eliminate the need for the browser to fetch multiple files, reducing load times and improving application responsiveness. This resolves the issues discussed above while still allowing developers to have a modular and scalable codebase.

## Limitations of Bundling

As the application grows in size, so does the size of the bundled file which again leads to a considerable delay in fetching and loading the bundled file. This defeats the purpose of bundling. That's where "Code Splitting" comes in to save the day!

## Code Splitting: The Key to Efficient Loading

Code splitting is a technique that breaks down the big bundled file into smaller, manageable chunks. So you may be wondering how is it different from our initial state where we had multiple files and modules. In code splitting, each page is linked to certain chunks of code which are required to load that page. This enables us to implement lazy loading on our webpage, which means only the code necessary for a page to load is fetched. This is done by fetching these small chunks in parallel. This ensures quick loading time and a responsive experience. This process is further optimized by techniques like prefetching the code for linked pages.

## Harnessing the Power of Bundling and Code Splitting

With numerous web bundlers available on the market, you'll be able to find one that caters to your project's specific needs and level of expertise.

Some popular JavaScript bundlers include:

1. [Webpack](https://webpack.js.org/)
2. [Browserify](https://browserify.org/)
3. [ESBuild](https://esbuild.github.io/)
4. [Parcel](https://parceljs.org/)
5. [Rollup](https://rollupjs.org/)

Most modern bundlers also support code splitting, and frameworks such as ReactJS and NextJS even offer additional support for this technique. The same can be reviewed in the articles given below.

1. [Code-splitting in Webpack](https://webpack.js.org/guides/code-splitting/)
2. [Code-splitting in Parcel](https://parceljs.org/features/code-splitting/)
3. [Support for code-splitting in ReactJS](https://reactjs.org/docs/code-splitting.html)
4. [Support for code-splitting in NextJS](https://nextjs.org/learn/foundations/how-nextjs-works/code-splitting)

Start optimizing your codebase today and experience the difference for yourself!