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Payment Notifications (POSTBACK)

POSTBACK: configuration, authenticity verification, and notification history for payment status.

POSTBACK is a notification that Trybit sends to the URL specified by the merchant (Notification URL / callback URL) whenever an invoice's status changes. This is the primary way to learn about a payment automatically, without manually polling the API.

How to configure It

The Notification URL is specified in the project's integration settings — in the "Notification URL" field (available only in test mode, see Project Settings).

How It works

  1. An invoice is created — manually, via API, or through any other integration method.

  2. The customer pays the invoice.

  3. Trybit sends a POSTBACK to the project's Notification URL — with invoice data: status, invoice number (INV), payment amount and currency, and your internal order_id (if it was passed when creating the invoice).

  4. Additionally, invoice status can be checked at any time via the API by invoice number (INV) — the invoice-information method lets you request up to 100 invoices in a single call.

How to verify a notification's authenticity

Every POSTBACK contains a signed token (JWT, HS256 algorithm) valid for 5 minutes from the time it's sent. On the merchant's side, you need to verify this token using your project's Secret key — this confirms that the notification genuinely came from Trybit and wasn't forged.

One common cause of webhook-related issues is a time mismatch on the merchant's server: if the server clock is more than a few minutes off, the token falls outside the 5-minute window and is considered invalid. This is the first thing to check when troubleshooting missing postbacks.

POSTBACK history

Your personal dashboard has a "Postback History" section — here you can see whether a postback was delivered successfully, and resend it if needed (including for invoices that were paid during test mode, even after exiting it).

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