esbuild-plugin-babel-cached

0.2.3 verified Sat Apr 25 auth: no javascript

esbuild-plugin-babel-cached (v0.2.3) is an esbuild plugin that runs files through Babel for transforms not supported natively by esbuild, with built-in caching. It wraps @babel/core and allows configuration via babel.config.json or inline options. Unlike other esbuild Babel plugins, it caches results to speed up rebuilds. The plugin is stable with weekly releases and is intended for scenarios where esbuild's own transforms (e.g., newer JavaScript/TypeScript) are insufficient and you need Babel for specific presets or plugins (e.g., for legacy browser support or custom transforms). It depends on @babel/core as a peer dependency and is ESM-only.

Common errors

error Error [ERR_REQUIRE_ESM]: require() of ES Module /path/to/esbuild-plugin-babel-cached/index.js from /path/to/project/esbuild.config.js not supported. ↓

cause Using CommonJS require() with an ESM-only package.

fix

Convert config file to ES module: rename to .mjs or add "type": "module" in package.json. Then use: import babel from 'esbuild-plugin-babel-cached'

error TypeError: (0 , _default) is not a function ↓

cause Named import instead of default import.

fix

Use: import babel from 'esbuild-plugin-babel-cached' (no curly braces)

error Error: Cannot find module '@babel/core' ↓

cause Missing peer dependency @babel/core.

fix

Install: npm install @babel/core -D

Warnings

breaking The plugin is ESM-only and cannot be loaded via require(). ↓

fix Use ES module imports (import babel from ...) and set "type": "module" in package.json or use .mjs extension.

deprecated The `config` option accepts Babel configuration; placing options in babel.config.json is also supported, but inline config takes precedence. ↓

fix If using babel.config.json, ensure it is in the project root or set rootMode: 'upward' in config.

gotcha If you target es5 with esbuild's own target option, Babel may not transform output if esbuild already handles it; ensure the Babel plugin runs before esbuild's internal transforms. ↓

fix Set esbuild target to the desired output (e.g., 'es5') to let esbuild handle what it can, and use Babel for additional transforms that esbuild doesn't support.

gotcha Caching may cause stale results if Babel config changes; clear cache by deleting node_modules/.cache/esbuild-plugin-babel-cached or setting CACHE_DIR environment variable. ↓

fix Set process.env.CACHE_DIR to a temporary directory or disable caching by passing cache: false to babel() options.

Install

npm install esbuild-plugin-babel-cached

yarn add esbuild-plugin-babel-cached

pnpm add esbuild-plugin-babel-cached

Imports

babel

wrong

const babel = require('esbuild-plugin-babel-cached')

correct

import babel from 'esbuild-plugin-babel-cached'

ESM-only package; CommonJS require() will fail.

babel

wrong

import { babel } from 'esbuild-plugin-babel-cached'

correct

import babel from 'esbuild-plugin-babel-cached'

Default export only; named export does not exist.

plugin type (TypeScript)

import type { Plugin } from 'esbuild'; import babel from 'esbuild-plugin-babel-cached'; const plugin: Plugin = babel();

TypeScript types are not shipped; you may need to define your own type or use @types/esbuild.

Quickstart

Minimal esbuild build with Babel caching plugin and custom Babel config.

import esbuild from 'esbuild';
import babel from 'esbuild-plugin-babel-cached';

await esbuild.build({
  entryPoints: ['src/index.ts'],
  bundle: true,
  outfile: 'dist/bundle.js',
  plugins: [babel({
    filter: /\.(js|ts)$/,
    config: {
      presets: ['@babel/preset-env'],
      plugins: ['@babel/plugin-transform-arrow-functions']
    }
  })],
  target: ['es5']
});