MarsSeed [1] filed a deletion request for mono-alpha [2]: This package is on the stable release from 2021-02-22. Current stable is much newer. Alpha release channel is no longer available, only Nightly, Preview, Stable, and Visual Studio. [a] [a]: https://www.mono-project.com/download [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/mono-alpha/