Changelog

2026-10-08 — Rejected invoices#

Invoice status gains the final value rejected: a timely payment cannot be accepted and nothing was accepted on the invoice; the status stays rejected even if money is accepted later. If part of the amount was already accepted, the invoice closes as underpaid instead. No reason is published.
Added the invoice.rejected webhook. Subscribe your endpoints to it under Developers → Webhooks & deliveries.
The change is additive. If you parse invoice status as a strict enum, including in invoice.payment_reversed and invoice.late_payment payloads and the status list filter, accept the new value. See payments that take longer.

Dashboard refunds return each payment to its verified sender. All returns appear in /v1/refunds; filter by invoice_id, identify payments with payment_id, and group returns with refund_request_id.
Invoices include refund_summary and support refund_status filtering.
Added refund.reversed, conversion.completed, conversion.failed, and conversion.source_restored webhooks.
Clarified currency errors, pagination, webhook source IP, and recovery after uncertain outcomes.
The merchant SDK is retired; its repository is archived. Use the supported REST API and HTTP/webhook examples.

Unified /v1 API: environment-specific keys, permissions, idempotency, and cursor pagination.
Added payout funding from other balances, conversions, and account operations.
Documented signed webhooks, dashboard-managed keys and subscriptions, HTTP examples, and errors.