v0.0.27 is a macOS / AppKit release.
That is the supported path. Other platforms are not recommended; wait for a later version.
facet_gtk
Not recommended on v0.0.27. This version is a macOS / AppKit release. Other platforms exist in the tree; do not ship on them yet. See the manual overview.
facet's GTK 4 backend: the Linux counterpart of facet_appkit. It fills the same Renderer vtable. facet owns the tree and layout; this package maps each kind to a typed gtk4 widget.
Status: type-checked, not run. cpc check is clean in this package's files. It links libgtk-4, so it has not been built or run in the compiler checkout. facet_appkit is the reference implementation.
import "facet_gtk/facet_gtk" as backend;
Install the backend, then runtime::App::run as on macOS. Real: label, button, identity. Partial: text area. For the generated GTK types themselves, see gtk4.