It would seem you currently cannot install gui-wm/sway-9999 with gui-libs/wlroots-9999, though they're part of the same project, as sway's ebuild contains: if [[ ${PV} == 9999 ]]; then DEPEND+="~gui-libs/wlroots-9999:=[elogind=,seatd=,systemd=,X=]" But wlroots-9999's ebuild contains: IUSE="x11-backend X" So any attempt to install them, irrespective of your USE flags yields: emerge: there are no ebuilds built with USE flags to satisfy "~gui-libs/wlroots-9999:=[elogind=,seatd=,systemd=,X=]". !!! One of the following packages is required to complete your request: - gui-libs/wlroots-9999::gentoo (Missing IUSE: elogind seatd systemd) (This is my first time actually reading the gentoo spec on how dependencies are written in ebuilds, so apologies if I'm misunderstanding something.
Was already fixed in: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=ad9a776356050f71bcd65cae2a4a6e913c6673f6 Is now: if [[ ${PV} == 9999 ]]; then DEPEND+="~gui-libs/wlroots-9999:=[X=]" Please emerge --sync and try again (may need to wait a bit for mirrors to update).
Ha! Good timing. That did indeed fix it; thank you.