Mustangserver 1.8.1

Version 1.8.0 of Mustangserver was released 18 December 2025, and supported ZUGFeRD 2.4 as well as styledinvoices, a way to exert full visual control on created Factur-X invoices.
Today, February 6th, 2026, we already released the subsequent version 1.8.1, which ships with a calculate endpoint, enabling e.g. invoice creation forms to easily obtain live previews of taxes and total amounts for users.

2.22.0

On February 4th, 2026, we released the new version 2.22.0 of our open source e-invoicing toolkit “Mustangproject”, which added minor features and multiple fixes.

New features

  • #1011 calculatedinvoice needs to contain VATtotal
  • #1010 add DeliveryNoteReferencedDocument per Item
  • #253/#994 add DeliveryNoteReferencedDocument for import and export
  • #536 support BT-18
  • #1000 Support ItemSellerTradeParty at line level (Factur-X / ZUGFeRD EXTENDED) for French municipalities subcontracting services to other municipalities

Fixes

  • #990 Fix empty ValidationResult when XMP metadata contains invalid XML characters
  • #859 SpecifiedTradePaymentTerms twice since version 2.16.5
  • #992 fix typo
  • #999 Write RateApplicablePercent on head also for tax free
  • #997 CategoryCode O Need VAT rate in header breakdown (BT-119) but MUST omit line VAT rate (BT-152)
  • #1003 IncludedNote SubjectCode PMD AAB
  • #998 ZUGFeRDInvoiceImporter does not properly handle UBL CreditNote documents
  • #1006 Duplicate Notes and Missing BIC Parsing in ZUGFeRDInvoiceImporter
  • #1017 Concurrency problems in ZUGFeRDDateFormat
  • deprecate itemTotalAllowances instead of itemAllowances over itemCharges
  • corrected import of UBL rounding amount

As usual, Mustangproject can be embedded in Java software using Maven Central, or downloaded as windows/linux/mac command line tool for free from it’s homepage.