MarsSeed [1] filed a deletion request for libuavcan [2]: Broken, deprecated library from 2018. Also upstream has been renamed to libcyphal. [a]
I advised the maintainer in January 2024 about this, and that only a 'libcyphal-git' package would be viable as successor on AUR, because upstream does not have git tags since the rename. [a]: https://github.com/UAVCAN/libuavcan [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/libuavcan/