The system was upgraded and everything is back online. If you experience any issues, please send an email to email@example.com - thanks a lot for your patience!
See #17 (closed) for more details, this allows me to install again under both Python 3.5.3 on my Debian laptop and Python 3.6.8 on CIT.
@GregAshton I'm not really fluent in packaging and all changes are ad-hoc hacks, so please have a careful look whether these are all reasonable.
This will create a new commit in order to revert the existing changes.