optional
@OptionalExpectation-annotated annotation classes declared in this module. Such classes are not materialized to bytecode on JVM, but the Kotlin compiler stores their metadata in the module file on JVM, and loads it during compilation of dependent modules, in order to avoid reporting "unresolved reference" errors on usages.
Multiplatform projects are an experimental feature of Kotlin, and their behavior and/or binary format may change in a subsequent release.