| [Updating the cart with the Store API](./rest-api/extend-rest-api-update-cart.md) | Update the server-side cart following an action from the front-end. |
| [Checkout Flow and Events](./checkout-payment-methods/checkout-flow-and-events.md) | All about the checkout flow in the checkout block and the various emitted events that can be subscribed to. |
| [Payment Method Integration](./checkout-payment-methods/payment-method-integration.md) | Information about implementing payment methods. |
| [Filtering Payment Methods](./checkout-payment-methods/filtering-payment-methods.md) | Information about filtering the payment methods available in the Checkout Block. |
In addition to the reference material below, [please see the `block-checkout` package documentation](../../../packages/checkout/README.md) which is used to extend checkout with Filters, Slot Fills, and Inner Blocks.
| [How the Checkout Block processes an order](./checkout-block/how-checkout-processes-an-order.md) | The detailed inner workings of the Checkout Flow. |
| [IntegrationInterface](./checkout-block/integration-interface.md) | The `IntegrationInterface` class and how to use it to register scripts, styles, and data with WooCommerce Blocks. |
| [Available Filters](./checkout-block/available-filters.md) | All about the filters that you may use to change values of certain elements of WooCommerce Blocks. |
| [Slots and Fills](./checkout-block/slot-fills.md) | Explains Slot Fills and how to use them to render your own components in Cart and Checkout. |
| [Available Slot Fills](./checkout-block/available-slot-fills.md) | Available Slots that you can use and their positions in Cart and Checkout. |
| [DOM Events](./checkout-block/dom-events.md) | A list of DOM Events used by some blocks to communicate between them and with other parts of WooCommerce. |
| [Filter Registry](../../../packages/checkout/filter-registry/README.md) | The filter registry allows callbacks to be registered to manipulate certain values. |
🐞 Found a mistake, or have a suggestion? [Leave feedback about this document here.](https://github.com/woocommerce/woocommerce-blocks/issues/new?assignees=&labels=type%3A+documentation&template=--doc-feedback.md&title=Feedback%20on%20./docs/third-party-developers/extensibility/README.md)