Config Options

🚧 Under Construction

We are working on generating a more detailed reference. For now, please refer to Rollup's Config Options Reference and documentation on additional notable features.

InputOptions

input

plugins

external

resolve

resolve.alias

WARNING

resolve.alias will not call resolveId hooks of other plugin. If you want to call resolveId hooks of other plugin, use aliasPlugin from rolldown/experimental instead. You could find more discussion in this issue

resolve.aliasFields

resolve.conditionNames

resolve.extensionAlias

Map of extensions to alternative extensions.

With writing import './foo.js' in a file, you want to resolve it to foo.ts instead of foo.js. You can achieve this by setting: extensionAlias: { '.js': ['.ts', '.js'] }.

resolve.exportsFields

resolve.extensions

resolve.mainFields

resolve.mainFiles

resolve.modules

resolve.symlinks

resolve.tsconfigFilename

cwd

platform

Expected platform where the code run.

shimMissingExports

treeshake

logLevel

onLog

onwarn

moduleTypes

experimental

experimental.enableComposingJsPlugins

experimental.strictExecutionOrder

experimental.disableLiveBindings

experimental.viteMode

experimental.resolveNewUrlToAsset

experimental.hmr

experimental.attachDebugInfo

define

Replace global variables or property accessors with the provided values.

Examples

• Replace the global variable IS_PROD with true

export default defineConfig({ define: { IS_PROD: 'true' // or JSON.stringify(true) } })

Result:

// Input
if (IS_PROD) {
  console.log('Production mode')
}

// After bundling
if (true) {
  console.log('Production mode')
}

• Replace the property accessor process.env.NODE_ENV with 'production'

export default defineConfig({ define: { 'process.env.NODE_ENV': "'production'" } })

Result:

// Input
if (process.env.NODE_ENV === 'production') {
 console.log('Production mode')
}

// After bundling
if ('production' === 'production') {
console.log('Production mode')
}

inject

Inject import statements on demand.

Supported patterns

{
  // import { Promise } from 'es6-promise'
  Promise: ['es6-promise', 'Promise'],

  // import { Promise as P } from 'es6-promise'
  P: ['es6-promise', 'Promise'],

  // import $ from 'jquery'
  $: 'jquery',

  // import * as fs from 'node:fs'
  fs: ['node:fs', '*'],

  // Inject shims for property access pattern
  'Object.assign': path.resolve( 'src/helpers/object-assign.js' ),
}

profilerNames

jsx

• false disables the JSX parser, resulting in a syntax error if JSX syntax is used.
• "preserve" disables the JSX transformer, preserving the original JSX syntax in the output.
• "react" enables the classic JSX transformer.
• "react-jsx" enables the automatic JSX transformer.

transform

Configure how the code is transformed. This process happens after the transform hook.

To transpile legacy decorators, you could use

export default defineConfig({
  transform: {
    decorator: {
      legacy: true,
    },
  },
})

For latest decorators proposal, rolldown is able to bundle them but doesn't support transpiling them yet.

watch

dropLabels

keepNames

checks

makeAbsoluteExternalsRelative

debug

debug.sessionId

preserveEntrySignatures

OutputOptions

dir

file

exports

hashCharacters

format

Expected format of generated code.

• 'es', 'esm' and 'module' are the same format, all stand for ES module.
• 'cjs' and 'commonjs' are the same format, all stand for CommonJS module.
• 'iife' stands for Immediately Invoked Function Expression.
• 'umd' stands for Universal Module Definition.

sourcemap

sourcemapDebugIds

sourcemapIgnoreList

sourcemapPathTransform

banner

footer

intro

outro

extend

esModule

assetFileNames

entryFileNames

chunkFileNames

cssEntryFileNames

cssChunkFileNames

sanitizeFileName

minify

name

globals

externalLiveBindings

inlineDynamicImports

advancedChunks

Allows you to do manual chunking. For deeper understanding, please refer to the in-depth documentation.

advancedChunks.minSize

• Type: number

Global fallback of {group}.minSize, if it's not specified in the group.

advancedChunks.maxSize

• Type: number

Global fallback of {group}.maxSize, if it's not specified in the group.

advancedChunks.maxModuleSize

• Type: number

Global fallback of {group}.maxModuleSize, if it's not specified in the group.

advancedChunks.minModuleSize

• Type: number

Global fallback of {group}.minModuleSize, if it's not specified in the group.

advancedChunks.minShareCount

• Type: number

Global fallback of {group}.minShareCount, if it's not specified in the group.

advancedChunks.groups

Groups to be used for advanced chunking.

advancedChunks.groups.name

• Type: string

Name of the group. It will be also used as the name of the chunk and replaced the [name] placeholder in the chunkFileNames option.

For example,

import { defineConfig } from 'rolldown';

export default defineConfig({
  advancedChunks: {
    groups: [
      {
        name: 'libs',
        test: /node_modules/,
      },
    ],
  },
});

will create a chunk named libs-[hash].js in the end.

advancedChunks.groups.test

• Type: string | RegExp | ((id: string) => boolean | undefined | void);

Controls which modules are captured in this group.

• If test is a string, the module whose id contains the string will be captured.
• If test is a regular expression, the module whose id matches the regular expression will be captured.
• If test is a function, modules for which test(id) returns true will be captured.
• If test is empty, any module will be considered as matched.

advancedChunks.groups.priority

• Type: number
• Default: 0

Priority of the group. Group with higher priority will be chosen first to match modules and create chunks. When converting the group to a chunk, modules of that group will be removed from other groups.

If two groups have the same priority, the group whose index is smaller will be chosen.

For example,

import { defineConfig } from 'rolldown';

export default defineConfig({
 advancedChunks: {
  groups: [
     {
       name: 'react',
       test: /node_modules/react/,
       priority: 1,
     },
     {
       name: 'other-libs',
       test: /node_modules/,
       priority: 2,
     },
  ],
});

This is a clearly incorrect example. Though react group is defined before other-libs, it has a lower priority, so the modules in react group will be captured in other-libs group.

advancedChunks.groups.minSize

• Type: number
• Default: 0

Minimum size of the desired chunk. If the accumulated size of the captured modules by this group is smaller than this value, it will be ignored. Modules in this group will fall back to the automatic chunking if they are not captured by any other group.

advancedChunks.groups.minShareCount

• Type: number
• Default: 1

Controls if a module should be captured based on how many entry chunks reference it.

advancedChunks.groups.maxSize

• Type: number
• Default: Infinity

If the accumulated size of the captured modules by this group is larger than this value, this group will be split into multiple groups that each has size close to this value.

advancedChunks.groups.maxModuleSize

• Type: number
• Default: Infinity

Controls a module could only be captured if its size is smaller or equal than this value.

advancedChunks.groups.minModuleSize

• Type: number
• Default: 0

Controls a module could only be captured if its size is larger or equal than this value.

legalComments

Control comments in the output.

• none: no comments
• inline: preserve comments that contain @license, @preserve or starts with //! /*!

plugins

polyfillRequire

hoistTransitiveImports

preserveModules

virtualDirname

preserveModulesRoot