How are payment gateways added as plug-ins (provider key, credentials, fees)?

Payment gateways are plug-ins: you add one by choosing its provider key and entering its credentials (API key/secret and any extra config), along with its fee structure (a percentage and/or fixed fee) and whether it's a BNPL provider. Multiple gateways can be configured, each enabled or disabled. Treating gateways as configurable plug-ins means adding a new payment method is a settings…

Payment gateways are plug-ins: you add one by choosing its provider key and entering its credentials (API key/secret and any extra config), along with its fee structure (a percentage and/or fixed fee) and whether it's a BNPL provider. Multiple gateways can be configured, each enabled or disabled. Treating gateways as configurable plug-ins means adding a new payment method is a settings task, not a development project — you provide the provider's details and it's available at checkout.