Tree-shaking
Tree-shaking is a build-time optimization that statically identifies and removes unused code from a program's output.
Web Components in Action
Tree shaking is static analysis that removes imported code and other module parts that are not used from a bundle.
- How it is used
- Reduces JavaScript bundle size during the build process by excluding unused imported modules.
- How deep it goes
- Defines import tracking and omission, then stops short of explaining the analysis algorithm or configuration details.
- Examples
- Uses an unused module and a banking application separating transaction and account-information bundles.
- What you can do after
- Apply it via Rollup or Webpack to create smaller bundles containing only needed module code.
The Joy of JavaScript
A bundler optimization that removes unused exports, modules, or code paths from a program during build time.
- How it is used
- Reduces bundled application payloads by eliminating unused modules and code during build time.
- How deep it goes
- Explains dependency analysis, ESM constraints, module design, and pure-call removal, but defers specific build-tool usage.
- Examples
- Uses unused exports, bundled dependency trees, and pure validation calls as removal examples.
- What you can do after
- Evaluate module designs and understand how ESM enables bundlers to remove unreachable code.
Related concepts
- CommonJScontrasts with · CommonJS is a JavaScript module-system specification that defines how modules export and load values, traditionally using synchronous require calls and module.exports assignments.
- Viteused by · Vite is a frontend development tool that provides a development server and production build pipeline for modern web applications.
- package.jsonconfigured by · package.json is the standard JSON manifest for an npm or Node.js package, declaring metadata, dependencies, scripts, entry points, and related configuration.
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