Unstable Api
@Target(allowedTargets = [AnnotationTarget.CLASS, AnnotationTarget.FUNCTION, AnnotationTarget.PROPERTY ] )
Opt-in marker for pre-release ("unstable") APIs. The API shape may still change and, in some cases, the effect is one-way and irreversible. Call sites must acknowledge with @OptIn(UnstableApi::class); when an API graduates the marker is dropped from it and — once the marker itself is removed — the opt-in fails to compile, forcing a migration to the stable form.