Hosted Payment SDK
If you have a Hosted Payments SDK (HPSDK) integration or an Active Merchant integration, then you can migrate your existing integration by building a new payments app on Shopify's Payments Platform. You can review the details of your HPSDK integration from the Partner Dashboard by clicking on Gateway integrations. For Active Merchant integrations, refer to the Active Merchant library on GitHub.
Explore the following resources to learn more about migrating your existing integration:
After you've built a new payments app, inform merchants of how and when they can install the new payments app. If you're offering multiple payments apps, then tell merchants which app to install to replace their current integrations.
Shopify will contact you directly with additional information to transition legacy integrations to the Payments Platform.