Today, May 28th, 2026, we released version 2.23.1 of our open source e-invoice toolkit “Mustangproject”, with two minor improvements:

• #1108 Regression Issue caused by empty XMP (introduced by #1076)
• #1120 ZUGFeRDImporter fails to extract Version if XML namespace is not exactly <rsm:CrossIndustryInvoice>

Some of the following changes were already part of the previous version, 2.23.0:

• – #1043 Fix percentage-based allowance/charge calculations
• – #1093 #814 upgrade CEN EN16931 Schematron from v1.3.12 to v1.3.15
• – #1102 Add BasisAmount to CashDiscount.
• – #1109 Feature fix xml description
• – #1110 Avoid NPE by checking zi.getXMP() is not null.
• – #1116 dont emit empty node for definedTradeContact
• – #1118 Support <ram:UltimateShipToTradeParty/>
• – #1119 Support <ram:DeliveryTypeCode/>