Issuing a structured invoice using the Open API of the National e-Invoice System (KSeF)

Issuing a structured invoice using the Open API of the National e-Invoice System (KSeF) The process of issuing an e-Invoice using the KSeF API is not trivial at all, which is why we have prepared the instructions below so that anyone who is not afraid can try their hand at this "competition". Anyway, there is no point in extending the introduction - see for yourself: 1. Challenge Read more…