# Custom Data Sources

Custom Data Sources let you enrich events with Shopify metafields and browser data.

Use them when the default Shopify event payload is not enough.

## Why use Custom Data Sources?

* Send a product `material` metafield to GA4.
* Use a customer `loyalty_tier` metafield in Klaviyo.
* Capture a cookie or local storage value for event enrichment.

## Set up Custom Data Sources

{% stepper %}
{% step %}

### Configure metafields

Go to **Settings → Custom Data Sources**.

<figure><img src="/files/CNGObjzDf6UeA2XpdtX9" alt=""><figcaption></figcaption></figure>

You will see **Customers**, **Products**, and **Product Variants**.

Littledata discovers available namespaces and keys automatically.

Select the metafields you want to expose in mappings.

<figure><img src="/files/QAU1wa6ztm4XkF3SpbUP" alt=""><figcaption></figcaption></figure>
{% endstep %}

{% step %}

### Configure browser data

In **Browser data**, add the cookie keys or local storage keys you want.

The Littledata tracking pixel will collect those values on supported events.

<figure><img src="/files/j7Q8hda2zEc72eAOigsV" alt=""><figcaption></figcaption></figure>

{% endstep %}

{% step %}

### Use the fields in mappings

After setup, these fields appear in the source dropdown of the mapping editor.
{% endstep %}
{% endstepper %}

{% hint style="info" %}
If new metafields do not appear yet, use **Refresh metafields**.
{% endhint %}

## Supported metafield types

| Owner type       | Shopify object      | Available on events                           |
| ---------------- | ------------------- | --------------------------------------------- |
| Products         | Product metafields  | `product_viewed`, `add_to_cart`, order events |
| Product variants | Variant metafields  | Order events, `add_to_cart`                   |
| Customers        | Customer metafields | Order events, customer events                 |

## Browser data

Browser data is collected by the Littledata tracking pixel on client-side events.

Supported sources are **Cookies** and **Local storage**.

{% hint style="info" %}
Browser data is only available on client-side events, such as `page_view` and `add_to_cart`.
{% endhint %}

## Refresh metafields

{% stepper %}
{% step %}

### Start a refresh

Go to **Custom Data Sources** and click **Refresh metafields**.
{% endstep %}

{% step %}

### Wait for discovery

Littledata starts a new bulk operation.

New metafields usually appear within a few minutes.
{% endstep %}
{% endstepper %}


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