NextJS is a framework for creating server-rendered React applications quickly and efficiently. Still, it can come with a hefty bundle size for your application if you’re not careful about how you set things up.
Fortunately, there are steps that developers can take to reduce the complexity of their NextJS builds and thus cut down on the overall build size without sacrificing performance or stability.
What Is Bundling?
Before diving into potential solutions, let’s look at bundling. When developing an app, lots of code needs to be written. This results in files with larger sizes after it has been compiled - these collections of modules/files bundled all together form bundles.
The process used here is called “Bundling” where multiple items combined equate to 1 single file ready for usage on websites/applications upon downloading them from the server via HTTP requests over browsers as needed.
This creates advantages such as reducing fluctuation within connection speeds and helping keep track of different dependencies easier and more manageably. It also informs users about each component better since they don't lump everything into one massive pile.
How To Optimize Your Bundle Size Using NextJS?
Now let’s get into how you can reduce your Next bundle size quickly and efficiently:
Use Production Mode:
By default, the development mode of NextJS reduces optimization, which causes extra code bloat. Switch into production before deploying your site/applications and enable features such as minification & dead code elimination to ensure it's unnecessary in bundles.
Keep Routes Simple
To reduce bundle sizes, it is advisable to keep HTTP requests simple. This can be done by directly including small inline chunks of data into component files rather than importing them from another file or making an API call. This helps streamline routing logic and optimizes client-side caching techniques.
Leverage Code Splitting Techniques
The dynamic import() function calls within modules can help trim excess fat from nonessential chunks, regardless of the framework used. This allows for asynchronous chunk downloads, as unrelated bits are broken apart each time they are needed.
Page-specific polyfills can be identified via runtime DOM feature detection to avoid loading unnecessary bytes with every visit.
Furthermore, leveraging libraries such as lazy loaders for react images provides an even better level of granularity by deferring loads for individual image resources required per visit, thus saving both load times and people's bandwidth consumption.
Remove Unnecessary Dependencies
A great way to prevent unnecessary bundling of redundant resources in NextJS is ensuring anything added gets utilized inside the project context. Carry out this process early, as discarded items will not contribute to delivery efforts and may reduce bulk without consequences.
Utilize Dynamic Imports Sparingly
Ensure that dynamic import statements are not invoked excessively, resulting in a high volume of queries and a large payload being sent out. This can create additional strain on already overburdened networks and may impede performance.
Minify & Compress Assets
Compressing images alongside other script-based content such as HTML and CSS JS naturally helps lower total weight, taking loads off infrastructure and enabling higher throughput.
Conclusion
Reducing NextJS Bundle Size is not technically challenging. As a rule of thumb, we should use dependencies consciously and minimize network usage. With some knowledge about the functions, integrations, packages, and scripts present in our app, we can understand the impact bulkiness has upon experience.
