v0.0.27 is a macOS / AppKit release.
That is the supported path. Other platforms are not recommended; wait for a later version.
quartzcore
Generated QuartzCore / Core Animation binding (cpc-bindgen --framework QuartzCore --prefix CA --merge). Ships Layer (CALayer) so NSView.layer() is a real typed object.
import "quartzcore/quartzcore" as quartzcore;
Depends on objc. Links the QuartzCore framework. facet_appkit uses it for layer-backed paint.