Nuxt/docs/2.guide/2.directory-structure/1.plugins.md

---
navigation.icon: IconDirectory
title: "plugins"
description: "Nuxt reads the files in your plugins directory and loads them at the creation of the Vue application."
head.title: "plugins/"
---

# Plugins Directory

Nuxt automatically reads the files in your `plugins` directory and loads them at the creation of the Vue application. You can use `.server` or `.client` suffix in the file name to load a plugin only on the server or client side.

::alert{type=warning}
All plugins in your [`plugins/` directory](/docs/guide/directory-structure/plugins) are auto-registered, so you should not add them to your `nuxt.config` separately.
::

## Which Files Are Registered

Only files at the top level of the [`plugins/` directory](/docs/guide/directory-structure/plugins) (or index files within any subdirectories) will be registered as plugins.

For example:

```bash
plugins
 | - myPlugin.ts  // scanned
 | - myOtherPlugin
 | --- supportingFile.ts   // not scanned
 | --- componentToRegister.vue   // not scanned
 | --- index.ts  // currently scanned but deprecated
```

Only `myPlugin.ts` and `myOtherPlugin/index.ts` would be registered. You can configure [`plugins`](/docs/api/configuration/nuxt-config#plugins-1) to include unscanned files.

## Creating Plugins

The only argument passed to a plugin is [`nuxtApp`](/docs/api/composables/use-nuxt-app).

```ts
export default defineNuxtPlugin(nuxtApp => {
  // Doing something with nuxtApp
})
```

### Object Syntax Plugins

It is also possible to define a plugin using an object syntax, for more advanced use cases. For example:

```ts
export default defineNuxtPlugin({
  name: 'my-plugin',
  enforce: 'pre', // or 'post'
  async setup (nuxtApp) {
    // this is the equivalent of a normal functional plugin
  },
  hooks: {
    // You can directly register Nuxt app hooks here
    'app:created'() {
      const nuxtApp = useNuxtApp()
      // 
    }
  }
})
```

You can also use the `env` property to define the environments in which your plugin will run.

- **islands**
  - **default**: `true`
  - **description**: You can set this value to `false` if you don't want the plugin to run when rendering server-only or island components.

::alert
If you are using an object-syntax plugin, the properties may be statically analyzed in future to produce a more optimized build. So you should not define them at runtime. For example, setting `enforce: process.server ? 'pre' : 'post'` would defeat any future optimization Nuxt is able to do for your plugins.
::

## Plugin Registration Order

You can control the order in which plugins are registered by prefixing with 'alphabetical' numbering to the file names.

For example:

```bash
plugins/
 | - 01.myPlugin.ts
 | - 02.myOtherPlugin.ts
```

In this example, `02.myOtherPlugin.ts` will be able to access anything that was injected by `01.myPlugin.ts`.

This is useful in situations where you have a plugin that depends on another plugin.

::alert{type=info icon=💡}
In case you're new to 'alphabetical' numbering, remember that filenames are sorted as strings, not as numeric values. For example, `10.myPlugin.ts` would come before `2.myOtherPlugin.ts`. This is why the example prefixes single digit numbers with `0`.
::

## Loading strategy

By default, Nuxt loads plugins sequentially. You can define a plugin as `parallel` so Nuxt won't wait the end of the plugin's execution before loading the next plugin.

```ts
export default defineNuxtPlugin({
  name: 'my-plugin',
  parallel: true,
  async setup (nuxtApp) {
    // the next plugin will be executed immediately
  }
})
```

## Using Composables Within Plugins

You can use [composables](/docs/guide/directory-structure/composables) within Nuxt plugins:

```ts
export default defineNuxtPlugin((NuxtApp) => {
  const foo = useFoo()
})
```

However, keep in mind there are some limitations and differences:

**If a composable depends on another plugin registered later, it might not work.**

**Reason:** Plugins are called in order sequentially and before everything else. You might use a composable that depends on another plugin which has not been called yet.

**If a composable depends on the Vue.js lifecycle, it won't work.**

**Reason:** Normally, Vue.js composables are bound to the current component instance while plugins are only bound to `nuxtApp` instance.

## Automatically Providing Helpers

If you would like to provide a helper on the `NuxtApp` instance, return it from the plugin under a `provide` key. For example:

```ts
export default defineNuxtPlugin(() => {
  return {
    provide: {
      hello: (msg: string) => `Hello ${msg}!`
    }
  }
})
```

In another file you can use this:

```vue
<script setup lang="ts">
// alternatively, you can also use it here
const { $hello } = useNuxtApp()
</script>

<template>
  <div>
    {{ $hello('world') }}
  </div>
</template>
```

## Typing Plugins

If you return your helpers from the plugin, they will be typed automatically; you'll find them typed for the return of `useNuxtApp()` and within your templates.

::alert
If you need to use a provided helper _within_ another plugin, you can call `useNuxtApp()` to get the typed version. But in general, this should be avoided unless you are certain of the plugins' order.
::

### Advanced

For advanced use-cases, you can declare the type of injected properties like this:

```ts [index.d.ts]
declare module '#app' {
  interface NuxtApp {
    $hello (msg: string): string
  }
}

declare module 'vue' {
  interface ComponentCustomProperties {
    $hello (msg: string): string
  }
}

export { }
```

::alert{type=warning}
If you are using WebStorm, you may need to augment `@vue/runtime-core` until [this issue](https://youtrack.jetbrains.com/issue/WEB-59818/VUE-TypeScript-WS-PS-does-not-correctly-display-type-of-globally-injected-properties) is resolved.
::

## Vue Plugins

If you want to use Vue plugins, like [vue-gtag](https://github.com/MatteoGabriele/vue-gtag) to add Google Analytics tags, you can use a Nuxt plugin to do so.

First, install the plugin you want.

```bash
yarn add --dev vue-gtag-next
```

Then create a plugin file `plugins/vue-gtag.client.js`.

```ts
import VueGtag, { trackRouter } from 'vue-gtag-next'

export default defineNuxtPlugin((nuxtApp) => {
  nuxtApp.vueApp.use(VueGtag, {
    property: {
      id: 'GA_MEASUREMENT_ID'
    }
  })
  trackRouter(useRouter())
})
```

## Vue Directives

Similarly, you can register a custom Vue directive in a plugin. For example, in `plugins/directive.ts`:

```ts
export default defineNuxtPlugin((nuxtApp) => {
  nuxtApp.vueApp.directive('focus', {
    mounted (el) {
      el.focus()
    },
    getSSRProps (binding, vnode) {
      // you can provide SSR-specific props here
      return {}
    }
  })
})
```

::alert{type=warning}
If you register a Vue directive, you _must_ register it on both client and server side unless you are only using it when rendering one side. If the directive only makes sense from a client side, you can always move it to `~/plugins/my-directive.client.ts` and provide a 'stub' directive for the server in `~/plugins/my-directive.server.ts`.
::

:ReadMore{link="https://vuejs.org/guide/reusability/custom-directives.html"}