Quba is a
e-Invoice-Viewer
Open-source / Free / Cross-Platform
Viewer for electronic invoices
We are Quba
Mustang's focusses on the creation, validation and parsing of electronic invoices. Validation checks the syntax and also re-calculates important parts of these invoices and there is also a Software-As-A-Service REST API available. Quba covers the visual display for manual checks.
Linux version works again
The good news in the 1.5.1. release was, that the auto-update feature worked, for the first time ever. The bad news was, that the Linux-version
Quba 1.5.1
Today, May 1st, 2026, we released version 1.5.1 of our open-source e-invoice viewer Quba. This version fixes some minor issues, among others in it’s interface
Quba 1.5.0
Quba 1.5.0 unterstützt auch ZUGFeRD 1 und bringt eine Suche und ein Handbuch.
Quba on the FOSDEM
On the FOSDEM in Brussels Quba had a little guest appearance in the talk Europe’s Way to Mandatory B2B-E-Invoices of which a recording is available.
Chat under the christmas tree
In order to mutually ask and answer questions Jochen suggests to just meet at the matrix.org #facturx room the next two Thursdays (26.12. and 02.01.)
Chat under the christmas tree
In order to mutually ask and answer questions Jochen suggests to just meet at the matrix.org #facturx room the next three Thursdays (19.12., 26.12. and
What about the name? Apart from being the name of a city in Azerbaijan, it also is the name of the horse breed originating from there. This name, like other horse names (Konic, Mustang) is a homage to the initiator of Factur-X / ZUGFeRD, the Forum of the Electronic Invoice Germany (“FeRD”, an accoustic allusion to the German word for horse).
Thank you for your support with the development of version 1.0
From now on community support and news are available via the ZUGFeRD Google Group.


