Credentials
- Sandbox account created and merchant-token issued.
- merchant_id and merchant_site_id recorded per environment.
- Tokens stored as server-side secrets, never in client code.
Methods, currencies and countries
- List the payment methods you need and confirm each is enabled on your account.
- Map every market to its currency and ISO-3 country code.
- Decide which flows are direct card payments, tokenized payments or payouts.
Redirect URLs
- success_url, pending_url, fail_url and back_url are publicly reachable.
- Each landing page reads the final state from your own backend, not from the URL alone.
Webhooks
- notification_link is an HTTPS endpoint reachable from the public internet.
- Handler responds 2xx fast and processes asynchronously.
- Processing is idempotent on request_id.
Sandbox tests
- Approval, decline and pending outcomes all handled.
- Status polling used only as a fallback to the notification.
- Payout flow tested if you send funds back to consumers.
Go-live readiness
- Production credentials and base URL swapped through configuration, not code edits.
- Reconciliation and monitoring in place before the first live transaction.