How can I register such a class in `SerializersMod...

# serialization

[spand]

How can I register such a class in SerializersModule { } (or why do I even need to?):

interface EnumMapping<K : Enum<K>, V> : Map<K, V>

@Serializable
data class EnumMappingImpl<K : Enum<K>, V>(
        private val backingMap: Map<K, V>,
) : EnumMapping<K, V>, Map<K, V> by backingMap

I have tried a polymorphic but it complains when using an instance of a @Serializeble class as key.

SerializersModule {
    polymorphic(EnumMapping::class) {
        subclass(EnumMappingImpl.serializer(PolymorphicSerializer(Any::class), PolymorphicSerializer(Any::class)))
    }
}