> Deprecated:
> Starting April 30, 2022, new users can no longer install your legacy Hosted Payment SDK (HPSDK) integrations. Your new payments app should be launched by this time to ensure that there's no disruption with new user onboarding. Existing users will have until July 31, 2022 to switch to your payments app.
>
> In early May 2022, Shopify will contact impacted users who haven't migrated to the new platform to help them adopt an alternative payments app and avoid payment processing disruptions. After July 31, 2022, all HPSDK integrations will be deprecated.

> To learn more about the HPSDK deprecation, and how to migrate to Payments Platform, refer to [Hosted Payment SDK overview](/docs/apps/build/payments/hosted-payment-sdk).


> Learn more about the new [payments platform](/docs/apps/build/payments).



The API Reference files give you all the `x_` **Keys**, e.g. `x_amount`, tell you if they are required values or not, and include short descriptions to provide some context.

- [**Request** values](/docs/apps/build/payments/hosted-payment-sdk/reference/request-values)

- [**Response** values](/docs/apps/build/payments/hosted-payment-sdk/reference/response-values)

If you're not yet ready to use the API reference material, you can start from the beginning with our [Hosted Payment SDK Overview](/docs/apps/build/payments/hosted-payment-sdk).