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Process Payments Through Configured Gateways

Process Payments Through Configured Gateways

Build a payment service that can process transactions through different gateways—Stripe, PayPal, or crypto—selected dynamically at runtime.

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Problem statement

Your e-commerce team is rolling out multi-provider payments. Some regions support Stripe (credit cards), while others use PayPal, and a few utilize crypto payments.

Checkout systems often hardcode payment gateway logic with conditionals like:

if (method === 'stripe') { /* Stripe logic */ }
else if (method === 'paypal') { /* PayPal logic */ }
else if (method === 'crypto') { /* Crypto logic */ }

Every time a new gateway is added, developers must modify this block and redeploy. You’ve decided to ...