Quba is a

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 also re-calculates important parts of these invoices. Quba covers the visual display for manual checks.

Quba 1.2.1

This version switches to the latest Mustangserver for invoice validation and updates Electron, allowing Quba to run on more recent Mac OS operating systems.

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Version 1.2.0 of the free e-invoice-viewer Quba, published on September 26th, 2022, continues to work offline, but can now also on demand connect to the

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Quba 1.1.5

Version 1.1.5 of the open-source e-invoice-viewer Quba, released 2022-08-18, now also supports embedded invoice accompanying files >6MB.

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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.