# Common Backend Flows

#### Issuance Flow

1. Collect KYC data from your frontend and validate it against your compliance rules.
2. Call `cardClient.createCard(...)` with the validated payload.
3. Store the returned card ID alongside your internal user record.
4. Present the masked card details to the user in your UI.

#### Secure Reveal Flow

1. Authenticate the user on your backend and confirm they own the requested card ID.
2. Call `cardClient.revealCard("card-id")`.
3. Stream the PAN, CVV, and expiry to the frontend over a short-lived secure channel (e.g. an encrypted WebSocket frame or a one-time-use endpoint).
4. Display the credentials in a non-copyable, auto-dismissing overlay.

#### Freeze / Replace Flow

1. Read the current card status from your internal records.
2. If the user requests a temporary hold, call `cardClient.setFreeze("card-id", true)`.
3. If the card is compromised or expired, call `cardClient.replaceCard("card-id", { renewOption })` and update your records with the new card ID.


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