# Custom Modules
> Custom Modules are completely open-ended components that allow you to create new experiences within the Directus
> platform. [Learn more about Modules](/getting-started/glossary/#modules).
## Extension Entrypoint
The entrypoint of your module is the `index` file inside the `src/` folder of your extension package. It exports a
configuration object with options to configure the behavior of your module. When loading your module, this object is
imported by the Directus host.
Example of an entrypoint:
```js
import ModuleComponent from './module.vue';
export default {
id: 'custom',
name: 'Custom',
icon: 'box',
routes: [
{
path: '',
component: ModuleComponent,
},
],
};
```
#### Available Options
- `id` — The unique key for this module. It is good practice to scope proprietary modules with an author prefix.
- `name` — The human-readable name for this module.
- `icon` — An icon name from the [material icon set](/getting-started/glossary/#material-icons), or the extended list of
Directus custom icons.
- `color` — A color associated with the module.
- `routes` — Details the routes in your module. The routes are registered as nested routes with the module's `id`
serving as the base path.
- `hidden` — A boolean that indicates if the module should be hidden from the module bar.
- `preRegisterCheck` — A function that receives the current user as the first parameter and the permissions of this user
as the second parameter. It should return a boolean that indicates if the check succeded.
## Routes Array
The `routes` array of a module works very similar to Vue Router's `routes` array. The only difference is that the
module's routes are registered as child routes of the `/` route.
The `routes` array should contain one or more route objects with a `path` property. Because the routes are registered as
child routes, the `path` property should be a relative path without a leading slash. As the button in the module bar
corresponding to your module links to the `/` route, the `routes` array should contain a _root_ route with an
empty path.
If a route should render something, the route object should have a `component` property with a reference to a route
component.
To learn more about the properties of route objects, you can refer to the
[Vue Router Docs](https://next.router.vuejs.org/guide/).
## Route Component
A single module can have multiple route components registered under different routes. Whenever a certain route is
visited, the corresponding route component is rendered, occupying the whole browser window. The route component has to
be Vue component. The most straightforward way to write a Vue component is to use the Vue Single File Component syntax.
Example of a route component using the Vue SFC syntax:
```vue
Content goes here...
```
A route component provides an blank canvas for creating anything you need. You can use the globally registered
`private-view` component to get access to Directus' page structure consisting of the module bar, the navigation, the
sidebar, the header and the main content area.
::: warning Enable the Module
Before a module appears in the module bar, it has to be enabled inside the project settings.
:::
::: warning Vue Version
The Directus App uses Vue 3. There might be 3rd party libraries that aren't yet compatible with Vue 3.
:::
## Accessing Internal Systems
To access internal systems like the API or the stores, you can use the `useApi()` and `useStores()` composables exported
by the `@directus/extensions-sdk` package. They can be used inside a `setup()` function like this:
```js
import { useApi, useStores } from '@directus/extensions-sdk';
export default {
setup() {
const api = useApi();
const { useCollectionsStore } = useStores();
const collectionsStore = useCollectionsStore();
// ...
},
};
```
::: tip Vue Options API
If you prefer to use the Vue Options API, you can inject the `api` and `stores` properties directly.
:::
## Example: Accessing the API from within your extension
The Directus App's Vue app instance provides a field called `api`, which can be injected into Vue components using
[Vue's inject framework](https://v3.vuejs.org/guide/component-provide-inject.html). This `api` field contains a property
called `api`, which is an authenticated Axios instance. Here's an example of how to use it:
```vue
{{ col.collection }}
Log collections to console
```
In the above example, you can see that:
- The `api` field gets injected into the component and becomes available as an attribute of the component (ie
`this.api`)
- When the component is mounted, it uses `this.api.get` to request a list of all available collections
- The names of the collections are rendered into a list in the component's template
- a button is added with a method that logs all the data for the collections to the console
This is just a basic example. A more efficient way to access and work with the list of collections would be to get an
instance of the `collectionsStore` using the provided `stores` and accessing `stores.useCollectionsStore()`, but that's
beyond the scope of this guide.