Poland
Poland e-invoicing API
Poland’s KSeF (Krajowy System e-Faktur) expects a national FA XML invoice, identified with NIP numbers. It is not an XRechnung and it is not Peppol BIS, even when you start from an EN 16931 model.
codecafe24 maps your JSON invoice into FA XML and validates it. Authentication and submission to KSeF remain in your integration.
Related
Questions
Which KSeF schema do you generate?
FA structured XML for the KSeF flow (FA(3) in the current generation). Confirm the schema version your gateway account requires before you go live.