supply

type Installer interface {
	InstallDependency(libbuildpack.Dependency, string) error
}

type Manifest interface {
	DefaultVersion(string) (libbuildpack.Dependency, error)
}

type Stager interface {
	AddBinDependencyLink(string, string) error
	DepDir() string
}

type Supplier struct {
	Stager    Stager
	Manifest  Manifest
	Installer Installer
	Log       *libbuildpack.Logger
}