What Verifactu is
"Verifactu" is the popular name for Spain’s Regulation on invoicing software systems, approved by Royal Decree 1007/2023. It does not create the duty to invoice: it sets out how invoicing software must work, so that every invoice is recorded, chained and cannot be altered. A system can also send each record to the Tax Agency at the moment of invoicing; that mode is called VERI*FACTU and it is the one FixrOS uses.