How do you analyze bundle size in a SvelteKit app?
Monitoring and optimizing bundle size in a SvelteKit app helps improve performance, reduce load times, and enhance user experience.
SvelteKit uses Vite under the hood, which provides a plugin called rollup-plugin-visualizer to inspect your bundle.
Install and Configure Visualizer
vite.config.js Example
After building your project (npm run build), the visualizer will open a report showing the size of each module in your bundle.
Vite supports a --report flag to generate a build report that can help identify large dependencies.
Generate Build Report
Tips:
Use dynamic imports to lazy-load rarely used components
Avoid importing entire libraries; import only what you need
Enable tree-shaking and code-splitting
Compress assets using gzip or Brotli
Monitor bundle size regularly using visualizer or similar tools