There's a history of German public administrations using Linux and other open-source software. In particular, the City of Munich has pioneered this with their 2006-2019 LiMux [0] project, which was ultimately cancelled in exchange for Microsoft moving their German offices to Munich proper.
[0]: https://en.wikipedia.org/wiki/LiMux / Discussion at https://news.ycombinator.com/item?id=15661372
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