Based on his Master thesis, Fabian Rechsteiner (cf. earlier) started Vectormap as a side-project. From the announcement (auto-translated):
The focus is on Swiss geodata, prepared as modern vector maps for web mapping applications. Instead of complex server infrastructures, I am concerned with pragmatic questions: How can geodata be used on the web in a high-performance, cost-efficient, and traceable manner?
Think: Procurement of official Swiss geodata in cloud-native formats.
Vectormap contains data from the Swiss cadastral survey1 (currently 2.3 GB), with monthly updates, thematically structured, and in PMTiles format. The data can be explored, for example, in the PMTiles Viewer. It can be used freely, with certain attributions. As far as I could see, the data production pipeline is not open-source.

Besides the vector data, Vectormap hosts map styles (currently, one), and example web maps using MapLibre.
Besides, the official website, Fabian publishes a LinkedIn newsletter for news and updates around the project. Both the website and the newsletter are in German. Feedback, questions, project or use-case ideas, suggestions for improvement are welcome.
Footnotes
… of most Swiss cantons. Cadastral survey data is not yet freely available in Vaud, Neuchâtel, Jura, Lucerne, Nidwalden, and Obwalden. The data in Vectormap.ch is sourced from geodienste.ch.↩︎
