> For the complete documentation index, see [llms.txt](/llms.txt).

# Lifecycle hooks

You can implement lifecycle hooks to automatically run an action, such as displaying a dialog or notification, when a user installs or updates your Snap.

## Steps[​](#steps "Direct link to Steps")

### 1. Request permission to implement lifecycle hooks[​](#1-request-permission-to-implement-lifecycle-hooks "Direct link to 1. Request permission to implement lifecycle hooks")

Request the [endowment:lifecycle-hooks](/snaps/reference/permissions/#endowmentlifecycle-hooks)permission. Add the following to your Snap's manifest file:

snap.manifest.json

```
"initialPermissions": {
  "endowment:lifecycle-hooks": {}
}

```

### 2. Run an action on installation[​](#2-run-an-action-on-installation "Direct link to 2. Run an action on installation")

To run an action when a user installs your Snap, expose the [onInstall](/snaps/reference/entry-points/#oninstall) entry point and implement the action. For example, you can use `onInstall` to perform any initialization that is required upon installation.

The following example displays an [alert dialog](/snaps/features/custom-ui/dialogs/#display-an-alert-dialog) upon installation:

- JSX
- Functions

index.tsx

```
import type { OnInstallHandler } from '@metamask/snaps-sdk'
import { Box, Heading, Text } from '@metamask/snaps-sdk/jsx'

export const onInstall: OnInstallHandler = async () => {
  await snap.request({
    method: 'snap_dialog',
    params: {
      type: 'alert',
      content: (
        <Box>
          <Heading>Installation successful</Heading>
          <Text>
            To use this Snap, visit the companion dapp at{' '}
            <a href="https://metamask.io">metamask.io</a>.
          </Text>
        </Box>
      ),
    },
  })
}

```

index.ts

```
import type { OnInstallHandler } from '@metamask/snaps-sdk'
import { heading, panel, text } from '@metamask/snaps-sdk'

export const onInstall: OnInstallHandler = async () => {
  await snap.request({
    method: 'snap_dialog',
    params: {
      type: 'alert',
      content: panel([
        heading('Installation successful'),
        text('To use this Snap, visit the companion dapp at [metamask.io](https://metamask.io).'),
      ]),
    },
  })
}

```

### 3. Run an action on update[​](#3-run-an-action-on-update "Direct link to 3. Run an action on update")

To run an action when a user updates your Snap, expose the [onUpdate](/snaps/reference/entry-points/#onupdate) entry point and implement the action. For example, you can use `onUpdate` to perform any migrations that are required upon update.

The following example displays an [alert dialog](/snaps/features/custom-ui/dialogs/#display-an-alert-dialog) upon update:

- JSX
- Functions

index.tsx

```
import type { OnUpdateHandler } from '@metamask/snaps-sdk'
import { Box, Heading, Text } from '@metamask/snaps-sdk/jsx'

export const onUpdate: OnUpdateHandler = async () => {
  await snap.request({
    method: 'snap_dialog',
    params: {
      type: 'alert',
      content: (
        <Box>
          <Heading>Update successful</Heading>
          <Text>New features added in this version:</Text>
          <Text>Added a dialog that appears when updating.</Text>
        </Box>
      ),
    },
  })
}

```

index.ts

```
import type { OnUpdateHandler } from '@metamask/snaps-sdk'
import { heading, panel, text } from '@metamask/snaps-sdk'

export const onUpdate: OnUpdateHandler = async () => {
  await snap.request({
    method: 'snap_dialog',
    params: {
      type: 'alert',
      content: panel([
        heading('Update successful'),
        text('New features added in this version:'),
        text('Added a dialog that appears when updating.'),
      ]),
    },
  })
}

```

## Example[​](#example "Direct link to Example")

See the [@metamask/lifecycle-hooks-example-snap](https://github.com/MetaMask/snaps/tree/main/packages/examples/packages/lifecycle-hooks)package for a full example of implementing lifecycle hooks.