Concepts

ZyndPay revolves around a small number of primitives. Once you know these, every API call fits into place.

Pay-in

Money coming from a customer into a merchant's USDT balance. A pay-in is typically created via a paylink and settles on TRON mainnet within ~60 seconds. Each pay-in can be refunded up to its remaining balance.

Payout

Money leaving the merchant's balance to a whitelisted destination (USDT address or mobile money account). Payouts require the destination to be pre-approved in the dashboard.

Withdrawal

A self-service payout where the destination is the merchant's own wallet. Subject to the same whitelist and compliance rules as any payout.

Refund

A reversal of a pay-in. Always bounded by the remaining balance of the original transfer — you can never refund more than was received.

Paylink

A signed URL that routes a customer into hosted checkout. Paylinks expire after their configured TTL and emit a payin.expired event on timeout.

Subscription

A recurring charge against a customer's stored instrument. Each renewal emitssubscription.renewed and produces a normal pay-in record.

Dispute

Raised when a customer or chain-analysis tool flags a payment. Disputes follow the escalation SLA tracked in issue #200.

Fees

Flat 1.5% of the pay-in amount. No setup cost, no monthly minimum. See the merchant pricing page for the binding agreement.