Mac here from Shopify. Thanks for reaching out in our Community forums. I’m happy to help.
There’re many different methods to consider when looking to become a Payment Provider. We have a very comprehensive guide that outlines the steps required to get started.
Firstly, you will need to become an approved Partner to build payments apps on Shopify's Payments Platform. This consists of three reviews: Payments Partner application review, Payments app extension review, and the Payments app review. You will then need to Create a payments app, and learn how to version and publish your app. Following this, you will need to Test an existing payments appwith a development store and a draft version. Then finally, you'll need to build a greatmerchant onboarding experiencefor your payments app.
I don't want to overwhelm you with information right now. So, let me know when you're done reading through those resources , and let me know if you have any questions!
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