How We Handled Offline Fiscalisation

Offline mode is one of the trickiest parts of MRA e-invoicing. Here is how we built it.

The challenge

The MRA endpoint is reachable over the internet. When it is not, you must still issue invoices. When it comes back, you must reconcile.

Our approach

1. Every invoice gets a sequential counter regardless of MRA status
2. The hash chain is calculated locally
3. A "Not Yet Fiscalised" placeholder is shown in the QR code area
4. A scheduler retries the MRA submission every 5 minutes
5. On success, the IRN and QR code are stored and the status updated