> For the complete documentation index, see [llms.txt](https://help.littledata.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.littledata.io/partner-recipes/rebuy/overview-integrating-littledata-with-rebuy.md).

# Overview: Rebuy integration

Top Rebuy integration for Google and Klaviyo

[Rebuy](https://www.rebuyengine.com/) adds personalized upsells, cross-sells and a Smart Cart to Shopify stores. This page explains how Littledata's connections work alongside Rebuy, with links to the setup guides.

### Klaviyo

Littledata's [Klaviyo connection](https://help.littledata.io/integrations/shopify-klaviyo) works alongside Rebuy's own [Klaviyo integration](https://www.rebuyengine.com/integrations/klaviyo). Littledata sends Shopify events such as viewed product, added to cart and placed order to Klaviyo server-side, so you can use them in Klaviyo segments and flows.

Shoppers don't need to be logged in to your store. When an event has no email or phone number, Littledata can use Klaviyo's own identifier for that browser to match the event to a known Klaviyo profile.

Learn more in [How it works: Shopify to Klaviyo](https://help.littledata.io/integrations/shopify-klaviyo/how-it-works-shopify-to-klaviyo).

### GA4 and the Rebuy Smart Cart

Littledata's [GA4 connection](https://help.littledata.io/integrations/shopify-to-google-analytics) tracks your Shopify store's sales and marketing data in GA4.

To also see how shoppers use the Rebuy Smart Cart, add a short script to your Shopify theme. It sends Smart Cart interactions to GA4 as events, such as when the cart is opened or closed, when an item quantity changes, or when an item is switched to a subscription. See [Track Rebuy Smart Cart in GA4](https://help.littledata.io/partner-recipes/rebuy/tracking-rebuy-smartcart).

### Google Ads and Meta Ads

Littledata's [Google Ads](https://help.littledata.io/integrations/google-ads/google-ads-how-it-works) and [Meta Conversions API](https://help.littledata.io/integrations/facebook-capi/how-it-works-shopify-to-meta-conversions-api) connections send your Shopify purchases to your ad platforms server-side. Ad platforms can then optimize your campaigns on complete purchase data.

### Related articles

* [Track Rebuy Smart Cart in GA4](https://help.littledata.io/partner-recipes/rebuy/tracking-rebuy-smartcart)
* [How it works: Shopify to Klaviyo](https://help.littledata.io/integrations/shopify-klaviyo/how-it-works-shopify-to-klaviyo)
* [How server-side tracking works](https://help.littledata.io/get-started/how-server-side-tracking-works)