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

# Building with the Unified API

In the Unified API model, **your engineering team drives everything**: you call Chift's endpoints directly and read or write your customers' financial data whenever your product needs to. Chift keeps the credentials working and gives you one consistent API shape across every connector.

New to the terms *connector*, *consumer*, and *connection*? See [How it works](/developer-guides/how-it-works) first.

## Who does what

* **You** create the consumer, create the connection, and hand the resulting activation link to your end-user. Afterwards you make the Unified API calls.
* **Your end-user** opens that link and authorizes access to their software — signing in via OAuth2, entering API credentials, or installing the local agent, depending on the connector. Some connectors then ask follow-up questions, such as which accounting folder or which POS location to use.
* **Chift** stores and refreshes the credentials, and exposes the data through one Unified API shape regardless of which connector is behind it.

<img src="https://mintcdn.com/chift/Fy9-9zDN2_VchWtm/assets/docs/developer-guides/unified_api_model.svg?fit=max&auto=format&n=Fy9-9zDN2_VchWtm&q=85&s=e010a16d7259754f8c92c25c9b33390b" alt="Unified API model" width="1200" height="440" data-path="assets/docs/developer-guides/unified_api_model.svg" />

## What you store

Just the **`consumerid`**. Keep it on your customer record: it is the key you pass to every Unified API call to say *whose* data you want.

You do not need to store connection IDs for normal use — Chift resolves the right connection from the consumer and the API you are calling. The exception is a consumer with two connectors serving the same Unified API, where you disambiguate with a header. See [Multiple connections per consumer](/developer-guides/unified-api/connections).

## The build path

<Steps>
  <Step title="Authenticate">
    Exchange your API key for a bearer token. See [Authenticate with Chift API](/developer-guides/chift-authentication).
  </Step>

  <Step title="Connect a customer">
    Create a consumer, create a connection, and send your end-user the activation link. See [Create a connection](/developer-guides/unified-api/how-to-connect).
  </Step>

  <Step title="Confirm and maintain the connection">
    Verify activation, then keep the connection healthy over time. See [Monitoring & updating connections](/developer-guides/monitor-connections).
  </Step>

  <Step title="Call the Unified API">
    Read and write data for the consumer through the relevant Unified API. Browse endpoints in the [API reference](/api-reference).
  </Step>
</Steps>

## In this section

<CardGroup cols={2}>
  <Card title="Create a connection" icon="link" href="/developer-guides/unified-api/how-to-connect">
    The full flow, from consumer to active connection.
  </Card>

  <Card title="Activation links & redirects" icon="arrow-right-arrow-left" href="/developer-guides/unified-api/activation-and-redirects">
    Control where your end-user lands after activation.
  </Card>

  <Card title="Monitor connections" icon="heart-pulse" href="/developer-guides/monitor-connections">
    Confirm activation and keep connections alive.
  </Card>

  <Card title="Multiple connections per consumer" icon="layer-group" href="/developer-guides/unified-api/connections">
    Two connectors serving the same Unified API.
  </Card>
</CardGroup>