Metro Minifier Terser

0.84.4 verified Fri May 01 auth: no javascript

Official Terser-based minifier plugin for Metro, the JavaScript bundler for React Native. Current stable version is 0.84.4, released ~monthly alongside Metro. Replaces the default metro-minify-uglify with modern ES6+ support via Terser. Key differentiator: integrates seamlessly with Metro's build pipeline, supports ES modules and modern syntax, and is the recommended minifier for React Native apps targeting ES6+ environments. Ships TypeScript type definitions since v0.83.5.

Common errors

error Error: Cannot find module 'metro-minify-terser' ↓

cause Package not installed or missing in node_modules.

fix

Run 'npm install --save-dev metro-minify-terser' or 'yarn add --dev metro-minify-terser'.

error TypeError: metroMinifyTerser is not a function ↓

cause Using default import incorrectly; package exported as a function in older versions.

fix

Check version: v0.84+ uses default export as a function; for older versions, use destructured import: const { minifier } = require('metro-minify-terser')

error Module 'metro-minify-terser' has no exported member 'minify' ↓

cause Attempting to import a non-existent named export.

fix

Import default: import metroMinifyTerser from 'metro-minify-terser' (v0.84+) or use: const metroMinifyTerser = require('metro-minify-terser').default (older CJS).

error Error: Terser minification failed: Unexpected token 'export' ↓

cause Minifier config ecma version too low (e.g., ecma: 5) while code uses ES modules.

fix

Set minifierConfig.ecma to 8 or above, and ensure module: true if using ES modules.

Warnings

breaking v0.84.0 dropped support for Node.js v21 and v23. Minimum Node version is now ^20.19.4 || ^22.13.0 || ^24.3.0 || >= 25.0.0. ↓

fix Upgrade Node to a supported version.

deprecated Metro 0.80+ has deprecated metro-minify-uglify in favor of this package. Terser provides better ES6+ support. ↓

fix Switch to metro-minify-terser as the minifier.

broken TypeScript types were missing in v0.83.0–v0.83.4 due to accidental removal. ↓

fix Upgrade to v0.83.5+ to restore TypeScript definitions.

gotcha If using custom minifier config, ensure it's valid for Terser. Invalid options (e.g., mismatched ecma version) may cause silent failures. ↓

fix Validate Terser options using Terser's own API before passing to Metro.

deprecated In Metro 0.84, the package became ESM-only. CommonJS require() will fail. ↓

fix Use import syntax or dynamic import() if needed.

Install

npm install metro-minify-terser

yarn add metro-minify-terser

pnpm add metro-minify-terser

Imports

default

wrong

const metroMinifyTerser = require('metro-minify-terser')

correct

import metroMinifyTerser from 'metro-minify-terser'

ESM-only since v0.84; no default export in older versions.

minify
wrong
```
import { minify } from 'terser'
```
correct
```
import { minify } from 'metro-minify-terser'
```
Named export for direct usage; consider Terser's own API for non-Metro use.

MetroMinifyTerser

import type { MetroMinifyTerser } from 'metro-minify-terser'

TypeScript type export; available in v0.83.5+.

Quickstart

Sets metro-minify-terser as the custom minifier in Metro's config with optional Terser options.

import metroMinifyTerser from 'metro-minify-terser';

// In metro.config.js:
module.exports = {
  transformer: {
    minifierConfig: { ecma: 8, module: true },
  },
  minifier: metroMinifyTerser,
};