#webpack

This section introduces how to migrate a webpack project to Rsbuild.

#Installing dependencies

First, replace webpack's npm dependencies with Rsbuild's dependencies.

• Remove webpack dependencies:

npm remove webpack webpack-cli webpack-dev-server

yarn remove webpack webpack-cli webpack-dev-server

pnpm remove webpack webpack-cli webpack-dev-server

bun remove webpack webpack-cli webpack-dev-server

deno remove npm:webpack npm:webpack-cli npm:webpack-dev-server

• Install Rsbuild dependencies:

npm add @rsbuild/core -D

yarn add @rsbuild/core -D

pnpm add @rsbuild/core -D

bun add @rsbuild/core -D

deno add npm:@rsbuild/core -D

#Updating npm scripts

Next, update the npm scripts in your package.json to use Rsbuild's CLI commands.

{
  "scripts": {
    "serve": "webpack serve -c webpack.config.js",
    "build": "webpack build -c webpack.config.js",
    "dev": "rsbuild dev",
    "build": "rsbuild build"
  }
}

#Create configuration file

Create an Rsbuild configuration file rsbuild.config.ts in the same directory as package.json, and add the following content:

import { defineConfig } from '@rsbuild/core';

export default defineConfig({
  plugins: [],
});

See Configure Rsbuild for more.

#Config migration

Webpack projects often include complex webpack.config.js configuration files.

After migrating to Rsbuild, most webpack configurations (such as output, resolve, and module.rules) are built-in and no longer require manual setup.

For the few webpack configurations that need to be migrated, you can choose the following options:

• Use the tools.rspack option (Rspack and webpack configurations are basically equivalent).

export default {
  tools: {
    rspack: {
      plugins: [new SomeWebpackPlugin()],
    },
  },
};

• Use the configuration helpers in Rsbuild; for example, you can set css-loader options through tools.cssLoader.

See Configure Rspack for more.

#Build entry

webpack uses the entry field to set the build entry. In Rsbuild, you can use source.entry to set it.

export default {
  source: {
    entry: {
      foo: './src/pages/foo/index.ts',
      bar: './src/pages/bar/index.ts',
    },
  },
};

#Cleaning up config

Because Rsbuild includes common loaders and plugins, you can remove the following dependencies to significantly speed up dependency installation:

• css-loader
• babel-loader
• style-loader
• postcss-loader
• html-webpack-plugin
• mini-css-extract-plugin
• autoprefixer
• @babel/core
• @babel/preset-env
• @babel/preset-typescript
• @babel/runtime
• ...

#Using plugins

Rsbuild offers a rich set of plugins that provide out-of-the-box support for common scenarios. You can refer to the Plugin List documentation to learn about these plugins.

For example, in a React project, you can integrate Rsbuild plugins as follows. First, remove React-related build dependencies that the Rsbuild React plugin already includes, such as:

• react-refresh
• @babel/preset-react
• @pmmmwh/react-refresh-webpack-plugin

Then follow the React Plugin documentation to register and use it as follows:

import { defineConfig } from '@rsbuild/core';
import { pluginReact } from '@rsbuild/plugin-react'; 

export default defineConfig({
  plugins: [pluginReact()],
});

Most common webpack loaders and plugins still work in Rsbuild, but we recommend prioritizing Rsbuild's plugins to simplify your configuration. The following shows how they map:

#Configure dev server

Rsbuild does not support Rspack's devServer config. See Rspack Dev Server for alternatives.

#Babel migration

Rsbuild uses SWC by default, so most commonly used Babel plugins are no longer required. Here are some common Babel plugins migration examples.

#@babel/preset-env

@babel/preset-env is no longer required, Rsbuild will automatically downgrade code based on the browserslist configuration.

Note that Rsbuild does not inject polyfill by default. You can refer to Polyfill mode for how to inject.

#@babel/preset-typescript

@babel/preset-typescript is no longer required, as Rsbuild enables SWC's TypeScript transformation by default.

#@babel/preset-react

@babel/preset-react is no longer required, replace it with @rsbuild/plugin-react.

#@babel/plugin-transform-runtime

@babel/plugin-transform-runtime is no longer required, Rsbuild has built-in equivalent @swc/helpers as runtime helpers.

#babel-plugin-import

babel-plugin-import can be replaced with the source.transformImport configuration in Rsbuild.

• Babel configuration:

module.exports = {
  plugins: [
    [
      'import',
      { libraryName: 'some-library', libraryDirectory: 'es', style: true },
    ],
  ],
};

• Rsbuild configuration:

export default {
  source: {
    transformImport: [
      { libraryName: 'some-library', libraryDirectory: 'es', style: true },
    ],
  },
};

#Validating results

After completing the above steps, you have completed the basic migration from webpack to Rsbuild. You can now run the npm run dev command to try starting the dev server.

If you encounter any issues during the build process, please debug according to the error log, or check the webpack configuration to see if there are any necessary configurations that have not been migrated to Rsbuild.

#Contents supplement

The current document only covers part of the migration process. If you find suitable content to add, feel free to contribute to the documentation via pull request 🤝.

The documentation for rsbuild can be found in the rsbuild/website directory.