> ## Documentation Index
> Fetch the complete documentation index at: https://langchain-5e9cc07a-preview-docsdy-1782337909-2539eb6.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Backend integrations

> Community-built filesystem backends for Deep Agents.

Browse available filesystem backends for Deep Agents or contribute your own to the ecosystem. Learn more about how backends work in the [backends docs](/oss/python/deepagents/backends).

## Share your backend

Custom backends connect Deep Agents to storage systems such as databases, object stores, and virtual filesystems. Share yours with the community:

<CardGroup cols={2}>
  <Card title="Implement a custom backend" icon="database" href="/oss/python/deepagents/backends#custom-backends">
    Follow the custom backends guide to build your own backend.
  </Card>

  <Card title="Share a community backend" icon="users" href="https://github.com/langchain-ai/docs">
    Open a PR to the docs repo to add your backend to the table below.
  </Card>
</CardGroup>

## Community integrations

<Note>
  The community maintains these backend integrations. They are contributed on an open-source basis and are not managed or maintained by LangChain.
</Note>

| Backend                                                                                              | Description                                                                                                                                                | Source                                                                                                                                        |
| ---------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------- |
| [MongoDB VFS Adapter](https://github.com/mongodb-developer/MongoDB-LangChain-DeepAgents-VFS-Adapter) | Virtual filesystem backend backed by MongoDB Atlas. Persist agent files, including memories, artifacts, and conversation history, in a MongoDB collection. | [`mongodb-developer/MongoDB-LangChain-DeepAgents-VFS-Adapter`](https://github.com/mongodb-developer/MongoDB-LangChain-DeepAgents-VFS-Adapter) |

Have a backend to share? [Open a PR](https://github.com/langchain-ai/docs) to add it here.

***

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