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Version: 1.0.0

Build For Production

By default, Farm has enabled support for the following features for production builds:

  • Tree Shake: Crop and filter irrelevant modules and code
  • Compression: Compress and mangle the output resources.
  • Automatically inject Polyfill: Farm downgrades to modern browsers(ES7) by default, if you need legacy browsers support, configuring targetEnv
  • Automatic partial packaging: Based on dependencies and size, the project is partially bundled. For each resource request, about 25 resources are generated to ensure parallel loading performance and improve cache hits rate as much as possible.

Configuring Output Dir​

Add build script in package.json:

"name": "1-create-a-project",
"version": "1.0.0",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"start": "farm start",
"build": "farm build",
"preview": "farm preview"
// ...ignore other fields

Then execute npm run build, the built resources will be emitted to build dir:

├─ favicon.ico
├─ index.html
├─ index_02bc.bd68e90b.js
├─ index_1c74.4b50f73e.js
├─ index_7734.440d56a3.js
├─ index_880b.4631ecee.js
├─ index_8d49.63f7b906.css
├─ index_9025.84e1f8e6.js
├─ index_ca37.f2c276ef.js
├─ index_ef2f.e25349d8.js
├─ index_f346.369a7312.js

If you want to custom the path that the resources emitted to, you can use:

import defineConfig from '@farmfe/core';

export default defineConfig({
compilation: {
output: {
path: 'build',
filename: 'assets/[name].[hash].[ext]',
assetsFilename: 'static/[resourceName].[ext]'

For above example, all js/css will be emitted to build/assets/(example: build/assets/index-ea54.abbe3e.js). All static assets like image will be emitted to build/static(example: build/static/background.png)

Preview Built Resources​

After the resources built, you can preview them by npm run preview:

$ npm run preview

> 3-build@1.0.0 preview
> farm preview

[ Farm ] Using config file at /root/tutorials/3-build-for-production/farm.config.ts
[ Farm ] preview server running at:

[ Farm ] > Local: http://localhost:1911/
[ Farm ] > Network:
[ Farm ] > Network:
[ Farm ] > Network:

open http://localhost:1911/ to preview your project.

Browser Compatibility​

By default, Farm build projects to Modern Browsers that natively support async/await:

  • Chrome >= 62
  • Firefox >= 63
  • Safari >= 13.1
  • Edge >= 79

You can use output.targetEnv to configuring your target browsers:

import { defineConfig } from '@farmfe/core';

export default defineConfig({
compilation: {
output: {
targetEnv: 'browser-legacy'

In above example, Farm will downgrade the syntax to es5 and inject polyfill automatically. Then we have to install core-js@3 to polyfill injection:

pnpm add -D core-js@3
  • You need to install core-js@3 manually if your target to legacy browsers.
  • If you want to configure browsers targets more precisely, see Syntax Downgrade And Polyfill

Configure Tree Shake and Minify​

Production optimization like treeShake and minify are disabled by default in development for performance reasons, and enabled by default in production. But if treeShake or minify are configured manually, the default value will be used regardless of development or production.

For details about tree shake and minify, see:

Configure Partial Bundling​


Refer to Partial Bundling for details.

Farm enabled best practice of bundling already, make sure you really need to configure bundles manually. See Partial Bundling for details.