# Common Frontend Flows

### Recommended Deployment Shape

KYC should always follow a **backend-first** pattern. The frontend never communicates directly with the KYC provider.

1. The frontend requests the backend to start a KYC session.
2. The backend calls `createApplicant` to create or fetch the applicant record.
3. The backend calls `createAccessToken` to mint a short-lived SDK token.
4. The backend returns the token to the frontend, which launches the provider's hosted verification flow.
5. The backend polls `getApplicantStatus` or processes provider webhooks to determine the verification outcome before unlocking downstream access (e.g. vault deposits, fiat on-ramps).

***

### Status Polling vs. Webhooks

For prototyping and low-traffic environments, polling `getApplicantStatus` on a short interval after the user completes the hosted flow is the simplest path. For production deployments, configure the provider's webhook endpoint to push status updates to your backend — this eliminates polling overhead and gives you real-time state transitions.

***

### Gating Access After Verification

Once `reviewResult.reviewAnswer` returns `GREEN`, your backend should persist the verification state against the user record. Use this persisted flag — not a live provider call — to gate access to protected features. If the answer is `RED`, surface the `rejectLabels` to your support tooling so the user can be guided through remediation. If the answer is `RETRY`, prompt the user to re-enter the hosted flow with a fresh access token.


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