KSeF API integration with ERP: architecture and most common errors
How to design integration that is resistant to data errors, delays and failures of external systems.
An integration architecture that scales
The most stable model is the queuing architecture, in which the ERP transfers documents to the integration layer, which handles communication with KSeF.
This arrangement isolates the transaction system from temporary problems with external services and allows operations to be repeated without blocking users.
- •Queues and retry with idempotence control.
- •Separation of validation from shipping.
- •Error logic in a dedicated website.
Errors that come back most often
A typical problem is the lack of a consistent document identifier between the ERP, middleware and the monitoring system. Without this, it is difficult to reconstruct the error history.
The second common mistake is not distinguishing between permanent and temporary errors, which leads to endless attempts to send the same faulty document.
- •No trace ID for documents.
- •Incorrect retry policy.
- •No separate queue for corrections and exceptions.
Monitoring and SLA
Implementing integration without operational metrics is risky. The company should monitor processing times, error rates, and team response times to incidents.
If this data is visible on the dashboard and combined with alerts, the team can react before the problem translates into accounting delays.
- •Document status dashboard.
- •Alerts about exceeded shipping times.
- •Weekly report of errors and causes.