# Common Frontend Flows

1. Call `paymentClient.getSupportedBlockchains({ currency })` to display available chains and currencies to the user.
2. Create a session with `paymentClient.createCryptoCheckout(...)`, passing the merchant reference, amount, currency, buyer info, and an expiry window.
3. Render the returned payment address and amount in your pay screen. Display the expiry countdown to the user.
4. Poll `paymentClient.getCryptoCheckout({ clientReference })` on an interval to track status transitions (e.g. pending → completed → settled).
5. On terminal status, update your order state and present the settlement confirmation to the user.

#### Recommended Integration Composition

For the best user experience, we recommend splitting payment data into two sources:

* **Client-side reads** (`getCryptoCheckout`, `getSupportedBlockchains`) for live status polling, chain discovery, and checkout rehydration.
* **Server-side writes** (`createCryptoCheckout`) for session creation, where `clientId` and `clientSecret` remain secure and are never exposed to the browser.


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