babel-preset-umi

1.8.4 verified Sat Apr 25 auth: no javascript

A Babel preset used internally by the Umi.js framework to transpile modern JavaScript/TypeScript and JSX for browser or Node targets. The latest stable version is 1.8.4, though it is tightly coupled with Umi major versions (e.g., Umi 4). It supports browserslist targets, polyfills via core-js, and optional transforms like Preact. Unlike generic presets (e.g., @babel/preset-env), this preset is designed for Umi's build pipeline and may include framework-specific optimizations. Release cadence follows Umi's release cycle. It is recommended to use this preset only within Umi projects.

Common errors

error Error: Cannot find module 'babel-preset-umi' ↓

cause Package not installed or Babel cannot resolve it.

fix

Run npm install babel-preset-umi --save-dev and ensure node_modules is correct.

error Invalid options object. Babel Preset has been initialized using an options object that does not match the API schema. ↓

cause Options placed outside of the preset's array wrapper.

fix

Correct format: presets: [['umi', { ... }]]

Warnings

gotcha Options object must be wrapped in an array: `['umi', options]` not `'umi', options`. ↓

fix Use `presets: [['umi', { ... }]]` in Babel config.

gotcha `browsers` option does not work if `targets` is specified. Only one should be used. ↓

fix Use either `browsers` or `targets`, not both.

deprecated This preset is tightly coupled with Umi.js; direct use outside Umi projects is not recommended and may break. ↓

fix Consider using @babel/preset-env with appropriate targets instead.

Install

npm install babel-preset-umi

yarn add babel-preset-umi

pnpm add babel-preset-umi

Imports

default (preset)
wrong
```
import umi from 'babel-preset-umi'
```
correct
```
module.exports = { presets: ['umi'] }
```
CommonJS module export, not ESM. Use string reference in Babel config.

Preset with options

wrong

presets: ['umi', { targets: { node: '6' } }]

correct

module.exports = { presets: [['umi', { targets: { node: '6' } }]] }

Options must be in an array: ['umi', options]

TypeScript usage

wrong

import { umi } from 'babel-preset-umi'

correct

// In .babelrc: { "presets": ["umi"] }

No named exports; always use string reference.

Quickstart

Configure babel-preset-umi in .babelrc or babel.config.js with browserslist targets and commonjs output.

module.exports = {
  presets: [
    ['umi', {
      targets: {
        browsers: ['last 2 versions']
      },
      commonjs: true,
      transformRuntime: false,
      preact: false,
      debug: false
    }]
  ]
};