Use YAML locale files in Nuxt 3

Have you ever tried loading YAML locale files inside your Nuxt 3 application using nuxt-i18n?

If you, did you come across the following error?

ERROR  Failed to parse source for import analysis because the content contains invalid JS syntax. You may need to install appropriate plugins to handle the .yaml file format, or if it's an asset, add "**/*.yaml" to assetsInclude in your configuration.

This article shows you how to properly setup Nuxt so it knows how to handle YAML files.

Configure Vite to handle YAML files

The above error message states that Vite doesn't know how to handle YAML files by default; it requires a plugin for that.

Install @modyfi/vite-plugin-yaml

See the package on

pnpm i -D @modyfi/vite-plugin-yaml
# or
# npm install -D @modyfi/vite-plugin-yaml
# or
# yarn add -D @modyfi/vite-plugin-yaml

Register the plugin

Then register the Vite plugin inside your Nuxt config file.

// nuxt.config.ts
import ViteYaml from '@modyfi/vite-plugin-yaml'

export default defineNuxtConfig({
  vite: {
    plugins: [

Add type definitions (optional)

Optionnaly, you can also add type definitions for .yaml or .yml modules.

// tsconfig.json
  "extends": "./.nuxt/tsconfig.json",

  "compilerOptions": {
    "types": [

Nuxt i18n configuration

Once Vite knows how to import yaml files, you can configure nuxt-i18n.

// i18n.config.ts
import en from './locales/en.yaml'
import fr from './locales/fr.yaml'

export default defineI18nConfig(() => ({
  messages: {

And voilà 🎉 You should now be able to use translations from YAML files!

BONUS: Lint your YAML files using ESLint

When I use YAML for my locale files, I like having my keys sorted alphabetically. For that, I'm using ESLint with yaml-eslint-parser.

I assume you already have setup ESLint in your project.

Install yaml-eslint-parser

pnpm i -D yaml-eslint-parser
# or
# npm install -D yaml-eslint-parser
# or
# yarn add -D yaml-eslint-parser

Configure ESLint

Once the YAML parser module has been installed, you need to instruct ESLint to use it on .yaml and .yml files.

// .eslintrc.cjs
module.exports = {
  overrides: [
      files: ['*.yaml', '*.yml'],
      parser: 'yaml-eslint-parser',
      extends: ['plugin:yml/standard'],
      rules: {
        'yml/sort-keys': [
            caseSensitive: true,
            natural: true,