Quba-viewer

Judgement

What it is

Complete system

What it does

A desktop viewer for electronic invoices such as ZUGFeRD, XRechnung and UBL that renders them readably and checks them.

Adopt it when

Someone in accounts receives XML e-invoices and needs to read and check them locally.

Watch out

A small project, and its documentation is partly copied from the ZUGFeRD-Manager it is based on.

Ready for

Usable

Runs as

Desktop app

Built with

Kotlin, Java and XSLT

How established

Established: started 5 years ago, latest release 2.0.0.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Compare Quba-viewer

Built from

Follow it down: Quba-viewer → Kotlin → JDK → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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