> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usebruno.com/llms.txt
> Use this file to discover all available pages before exploring further.

# YAML Migration

Starting with Bruno v3.1.0, new and imported collections use [OpenCollection YAML](/opencollection-yaml/overview) by default. If you have existing `.bru` collections, you can migrate them in a few steps.

<Note>
  All requests in a collection must use the same format. A collection cannot mix `.bru` and `.yml` files. Migration is available in Bruno v4.1.0 and higher.
</Note>

<Warning>
  Back up your collection before migrating. [Export the collection using the **Share**](/get-started/import-export-data/export-collections) option in the context menu of the collection to get a copy of the original `.bru` files.
</Warning>

## How to migrate

1. Open your `.bru` collection in Bruno.
2. Click **Migrate to YML** button available in the top-right navigation bar or in the bottom of the collection **Overview** tab.

<img src="https://mintcdn.com/bruno-a6972042/5Lfx5Y84o3IdcSG8/images/screenshots/v4/bru-yaml-migration/1-migrate-yml-option.webp?fit=max&auto=format&n=5Lfx5Y84o3IdcSG8&q=85&s=f1c79d0bfb8ee07631aa20ed3e28adbb" alt="Migrate to YML option" width="2608" height="1578" data-path="images/screenshots/v4/bru-yaml-migration/1-migrate-yml-option.webp" />

3. A confirmation dialog appears. Click **Export Collection** to back up your existing collection before proceeding.

<img src="https://mintcdn.com/bruno-a6972042/5Lfx5Y84o3IdcSG8/images/screenshots/v4/bru-yaml-migration/2-migration-button-with-backup.webp?fit=max&auto=format&n=5Lfx5Y84o3IdcSG8&q=85&s=f90cf6ecdeaed0ac088c84bc2af9a8f3" alt="Migration dialog with backup option" width="2608" height="1092" data-path="images/screenshots/v4/bru-yaml-migration/2-migration-button-with-backup.webp" />

4. Click **Migrate** to complete the migration. Your collection is now stored as `.yml` files.

## Before and after

<CodeGroup>
  ```bru Before (.bru) theme={null}
  meta {
    name: github-user
    type: http
    seq: 2
  }

  get {
    url: https://api.github.com/users/usebruno
    body: none
    auth: inherit
  }

  settings {
    encodeUrl: true
    timeout: 0
  }
  ```

  ```yaml After (.yml) theme={null}
  info:
    name: github-user
    type: http
    seq: 2

  http:
    method: GET
    url: https://api.github.com/users/usebruno
    auth: inherit

  settings:
    encodeUrl: true
    timeout: 0
    followRedirects: true
    maxRedirects: 5
  ```
</CodeGroup>

## After migration

* Your requests are now saved as `.yml` files with `opencollection.yml` at the collection root
* If any scripts use `bru.runRequest()` with a `.bru` file extension in the path, update those to `.yml`
* The original `.bru` files are removed after migration, so keep your backup until you confirm everything works

## Related

* [OpenCollection YAML overview](/opencollection-yaml/overview)
* [YAML structure reference](/opencollection-yaml/structure-reference)