So excuse my translation but for the Audience here in the US here goes:
The vision: processing data sets with arcs cleanly
Circular arcs are a central element in the surveying process, the clean handling of this is a mandatory prerequisite for working on and with data of official surveying. Complete support for arcs in the standard software QGIS will make it possible to use this application for a whole range of new application cases, both for the tracking of the official surveying and for working with data set-up data sets up on them, such as usage planning. QGIS already supports the collection and storage of arcs, but these are often lost when geometries are blended or merged. This leads to complex post-processing, we would like to ensure that QGIS does this for us: reliable, clean and error-free.
Crowdfunding is at the Bottom of the website (which appears to be in German according to Duck Duck go) : https://www.opengis.ch/crowdfunding-erweiterte-unterstutzung-fur-kreisbogen-in-qgis/