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

# Cart

> Server-persisted cart that holds products across sessions and devices, scoped to a project.

Colossal provides a standalone server-persisted cart primitive that can be used across sessions and devices.

Cart is scoped to a project, stores products and can be optionally linked to an existing customer.

## How to use

You can use it as part of the Colossal platform — alongside [products](/concepts/products) and [checkout](/concepts/checkout-and-payments) — or drop it into an existing platform to add a server-persisted cart on top of your own product catalog and checkout.

## Surfaces

<CardGroup cols={3}>
  <Card title="Events" icon="bolt" href="/apps/colossal-app/storefront-events#cart">
    Cart lifecycle events your automations can react to.
  </Card>

  <Card title="Actions" icon="play" href="/apps/colossal-app/storefront-actions#cart">
    4 actions for fetching and modifying carts.
  </Card>

  <Card title="Storefront API" icon="code" href="/api-reference/cart">
    GraphQL queries and mutations for your storefront.
  </Card>
</CardGroup>

## Real-time cart modifications

Carts can be modified in real time using cart automations. For example, you can automatically apply discounts, add free items, or validate cart contents before checkout. Cart automations run synchronously so the customer sees the result immediately.