babel-preset-env-modules

1.0.1 verified Sat Apr 25 auth: no javascript

A Babel preset that wraps @babel/preset-env and babel-polyfill-corejs3 to produce minimal compiled output for environments that support ESM, with improved polyfill handling. Current version 1.0.1, released as a single stable version. It solves the common issue where preset-env conflates helpers and polyfills, leading to unnecessary code. Key differentiators: automatically prevents inclusion of supported builtins, uses finer-grained polyfills via babel-polyfills, excludes niche polyfills (e.g., Symbol.species) by default, and coordinates options between preset-env and polyfill plugin to avoid conflicts. Suitable for library authors targeting modern browsers or Node.js with ESM.

Common errors

error Error: [BABEL] unknown preset 'babel-preset-env-modules' ↓

cause Preset not installed

fix

npm install babel-preset-env-modules --save-dev

error TypeError: Cannot read property 'preset-env' of undefined ↓

cause Missing @babel/preset-env peer dependency

fix

npm install @babel/preset-env --save-dev

Warnings

gotcha The polyfill option automatically sets corejs and useBuiltIns, overriding any manual settings passed to preset-env. ↓

fix Use polyfill option instead of manually setting corejs/useBuiltIns in preset-env options.

deprecated The package is essentially a wrapper that may become obsolete as @babel/preset-env and babel-polyfills improve. ↓

fix Consider migrating to direct use of @babel/preset-env with useBuiltIns: 'usage' and corejs option.

gotcha Setting modules to false (preserve ESM) may conflict with polyfill plugin if not careful; polyfill may still inject non-ESM code. ↓

fix Ensure polyfill option is configured to respect modules setting.

Install

npm install babel-preset-env-modules

yarn add babel-preset-env-modules

pnpm add babel-preset-env-modules

Imports

babel-preset-env-modules
wrong
```
import preset from 'babel-preset-env-modules'
```
correct
```
module.exports = { presets: [['babel-preset-env-modules', options]] }
```
This is a Babel preset, used in .babelrc or babel.config.js, not imported in application code.

DEFAULT

wrong

module.exports = { presets: [require('babel-preset-env-modules')] }

correct

module.exports = { presets: ['babel-preset-env-modules'] }

Presets are strings in Babel config, not require() calls.

Quickstart

Configure Babel with babel-preset-env-modules for ESM targets with polyfill support.

// babel.config.js
module.exports = {
  presets: [
    [
      'babel-preset-env-modules',
      {
        targets: { esmodules: true },
        loose: true,
        bugfixes: true,
        modules: false, // preserve ESM
        polyfill: {
          // see babel-polyfill-corejs3 options
          corejs: 3,
          proposals: true,
        },
      },
    ],
  ],
};