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

# Customer.io (Data Sync)

> Sync Customer.io campaigns and messaging activity into your warehouse.

Humm syncs your Customer.io data into your warehouse via Airbyte, then queries the synced copy through your warehouse integration. This is useful when you want marketing automation data alongside product, billing, and lifecycle data.

## Source Type

<Card title="Sync" icon="arrows-rotate">
  Humm copies Customer.io data into your warehouse on a schedule. Humm then queries the synced tables rather than calling Customer.io live.
</Card>

See [Choosing a Source Type](/integrations/overview#choosing-a-source-type) for help deciding.

## What Gets Synced

Customer.io sync can include:

* Campaigns
* Campaign actions
* Newsletters

## Credentials

<Card title="App API Key" icon="key">
  Connect using your Customer.io App API key.
</Card>

## Best For

* Measuring lifecycle messaging activity alongside product usage and conversions
* Reviewing campaign operations in a shared warehouse
* Joining marketing sends with account, revenue, or support trends