gammy [1] filed a orphan request for raptor-chess [2]:
The author has left this package broken for years. A user in the comments has offered to take over maintenance.
[1] https://aur.archlinux.org/account/gammy/ [2] https://aur.archlinux.org/pkgbase/raptor-chess/
Request #15301 has been accepted by polyzen [1].
aur-requests@lists.archlinux.org