Architecture
Modules
The debiX system is designed with a modular architecture, where each module operates independently and generates its own event notifications based on its specific business logic.
Unidirectional Communication
All module-generated notifications are delivered to the issuer via the MQ channel, which is strictly one-way. No response is expected or received through this channel. For two-way interactions or follow-up actions, issuers should use the debiX API.
When an event occurs, the system triggers a notification that is routed to the issuer through the configured MQ for the selected module.
Flow tracing
The event envelope of a push message will contain the issuer trace identifier from September 2026 onward, if it was given in the debix API request or the debix BULK message that triggered this push event. This allows to correlate the complete flow.
The issuer trace identifier may be given as
- request header
issuer-trace-idin debix API requests or - issuer trace identifier in the message envelope of debix BULK messages.
Setup Options
An issuer can subscribe to one or more MQs, depending on his integration preferences and the number of modules they wish to access.
- Single MQ Setup: All module notifications are delivered through a single queue.
- Multiple MQ Setup: Each module delivers notifications through a shared or dedicated queue.
This flexible setup allows an issuer to tailor the integration to his operational and technical needs.
Priority
Not all event notifications have the same level of importance. For example, a notification about a card being blocked is more critical than a notification about a new card order. To ensure important notifications are processed first, each event notification is assigned a priority level.
Priority levels range from 0 to 9, with 9 = highest priority, 0 = lowest priority.
When notifications are retrieved from the message queue, those with higher priority are always delivered first; so, they effectively overtake lower‑priority notifications.
| Event Notification | Priority |
|---|---|
| CARD_BLOCKED | 9 |
| CARD_UNBLOCKED | 8 |
| AUTHORIZATION_FULFILLED | 6 |
| AUTHORIZATION_REJECTED | 6 |
| CARD_UPDATED | 4 |
| CARD_DELETED | 4 |
| TOKEN_UPDATED | 4 |
| TOKEN_DECLINED | 4 |
| CARD_ORDERED | 3 |
| CARD_ORDER_REVERSED | 3 |
| PIN_ORDERED | 3 |
| PIN_VIEWED | 3 |
| ISSUE_OCCURRED | 1 |
| CARD_SYNC | 0 |