𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 𝗕𝘂𝗻𝗱𝗹𝗶𝗻𝗴 𝗘𝘅𝗽𝗹𝗮𝗶𝗻𝗲𝗱
You write React or Angular apps using many files. You use components, services, and libraries.
Browsers struggle with many files. Loading 200 files means 200 network requests. This makes your app slow.
Bundlers solve this. They take your code and imports and combine them into one or a few small files. This makes loading efficient.
Modern bundlers do more than combine files. They perform these tasks:
- Minification: They remove spaces and comments. They shorten variable names to save space.
- Tree shaking: They remove code you do not use.
- Code splitting: They split code into small chunks. Users only load what they need.
Smaller files lead to faster apps.
Two main tools exist: Webpack and Vite.
Webpack bundles your entire app before serving it. It is powerful and flexible. It can feel slow in large projects because it rebundles everything during changes.
Vite is a modern choice. It serves files directly during development using native ES modules. It updates only the file you change. This makes updates instant.
Comparison:
Webpack:
- Dev speed: Slower
- Config: Complex
- Best for: Large legacy projects
Vite:
- Dev speed: Fast
- Config: Simple
- Best for: New modern projects
Use Vite for new projects.
Every bundler follows three steps:
- Build a dependency graph: The bundler maps how files connect to each other.
- Transform code: It converts TypeScript or JSX into plain JavaScript.
- Output the bundle: It writes the final files to a folder for deployment.
Keep your bundle lean with these tips:
- Lazy loading: Load components only when a user needs them.
- Specific imports: Do not import entire libraries. Import only the specific functions you use.
- Analyze your bundle: Use tools to see which files take up the most space.
- Use production builds: Always deploy production builds instead of development builds.
Bundlers make your apps faster by providing fewer, smaller files.
Source: https://dev.to/kavya1205/javascript-bundling-explained-from-zero-to-optimised-f7p