I fixed the error reported by @pauljako that the login is not working anymore which is likely caused because of recent api changed by traewelling.
The travel mode (bus, train …) and the source/license of the checkin are now not always included so I set them to optional.

It was really difficult to debug because I couldn’t get serde to show the full problem … but it worked after some tries 🎉

(some licensing things: The background image in my terminal is the KDE Plasma workspace
wallpaper “Scarlet tree” made by axo1otl [email protected] and licensed CC-BY-SA 4.0. Repo: https://invent.kde.org/plasma/plasma-workspace-wallpapers/-/tree/master/ScarletTree
My screenshot is licensed CC-BY-SA 4.0)