Credit card checkout on Secondary Sales Marketplaces is currently facilitated by Sardine (with Transak and other payment service provider(s) support coming soon).

At a high-level, the way it works is that the payment service provider’s APIs/contracts are given the appropriate permissions to act upon the marketplace contract.

When the user is directed to the web-based checkout payment flow, we include the required transaction calldata for the payment service provider to execute. Upon completion of payment by the user, the payment service provider signs and executes the provided calldata - transferring your user the collectible(s).

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