esbuild-plugin-elm

0.0.12 verified Mon Apr 27 auth: no javascript

An esbuild plugin for building Elm projects, version 0.0.12. It integrates the Elm compiler into esbuild's build process, resolving imports via elm.json source-directories. Key features include debug mode, optimization based on NODE_ENV, watch mode support with console clearing, and custom path to Elm executable. Compared to alternatives like elm-webpack-loader or elm-parcel, this plugin is tightly coupled with esbuild, offering faster builds. It depends on esbuild >=0.8.1. Release cadence is irregular, last updated in 2022.

Common errors

error TypeError: ElmPlugin is not a function ↓

cause Incorrect import: const ElmPlugin = require('esbuild-plugin-elm') instead of .default

fix

const ElmPlugin = require('esbuild-plugin-elm').default

error Error: Plugin 'elm' failed: elm: command not found ↓

cause Elm compiler not installed or not in PATH

fix

Install elm globally or set pathToElm option to full path of elm executable

error error: No matching entry point found for 'src/Main.elm' ↓

cause Entry point file extension not recognized; use .js or .ts as entry, not .elm

fix

Use a JavaScript/TypeScript file as entry point that imports Elm modules

Warnings

gotcha Default export; named import fails ↓

fix Use default import: import ElmPlugin from 'esbuild-plugin-elm'

gotcha CommonJS require returns ESM module; must use .default ↓

fix Use const ElmPlugin = require('esbuild-plugin-elm').default

gotcha Path to Elm executable defaults to 'elm' in PATH; may fail if not installed globally ↓

fix Set pathToElm option to exact path of elm binary (e.g., require('elm'))

Install

npm install esbuild-plugin-elm

yarn add esbuild-plugin-elm

pnpm add esbuild-plugin-elm

Imports

ElmPlugin

wrong

const { ElmPlugin } = require('esbuild-plugin-elm')

correct

import ElmPlugin from 'esbuild-plugin-elm'

Default export; named export not available in CommonJS

ElmPlugin

wrong

const ElmPlugin = require('esbuild-plugin-elm')

correct

const ElmPlugin = require('esbuild-plugin-elm').default

CommonJS require needs .default due to ESM default export

ElmPlugin

wrong

import { ElmPlugin } from 'esbuild-plugin-elm'

correct

import ElmPlugin from 'esbuild-plugin-elm'

Named import is incorrect; it's a default export

Quickstart

Basic ESM usage of esbuild-plugin-elm with esbuild, showing import and configuration options.

import esbuild from 'esbuild';
import ElmPlugin from 'esbuild-plugin-elm';

await esbuild.build({
  entryPoints: ['src/index.js'],
  bundle: true,
  outfile: 'dist/bundle.js',
  plugins: [
    ElmPlugin({
      debug: false,
      optimize: process.env.NODE_ENV === 'production',
      pathToElm: 'node_modules/.bin/elm',
      clearOnWatch: false,
      verbose: false,
    }),
  ],
});
console.log('Build complete.');