… it features a shortened version of the VAT declaration form, coping with typical needs.
… it works out of the box, just unpack the ZIP archive and launch the application. No need to configure & make.
… it's free software. You don't have to rely on a black box doing the encryption of your private data. You get the source, just have a look into it.
Unfortunately it's still not possible to send returns that are due annually since the fiscal authorities don't allow to do that off the ERiC library (which is proprietary however). It's currently not clear whether one day it will be possible at all.
To mimic the look & feel of a desktop application it's based on Mozilla XUL, the engine used by the Firefox browser. This is, any system that's capable of running Firefox also is able to run Geierlein, …hence it should work on at least GNU/Linux, Windows & MacOS.
Here's a screenshot of the XUL-based application:
Geierlein is an essential part of Taxbird, a private project of me, Stefan Siegl. I started the project back in 2004, mainly as I was a tax accountant assistant ("Steuerfachangestellter") and therefore got a natural interest in the topic. Since I'm very much engaged with computers in general, and software development in particular, somewhen the question arose how the ELSTER-project works in detail and I regretted that there was no open source client for it…
Until today I've neither been a freelancer nor an entrepreneur, and therefore never have been obliged to file VAT declarations. Hence I never was actually able to use Geierlein in production. In case you consider the project useful, I'd very much appreciate a little donation to contribute to the development costs.