By using @get: you are telling the Kotlin Compiler to put the annotations on the Getter it generates for the data class property instead of the field. Since Kotlin duplicates fields, using field annotations is actually not a good idea. It’s so strange, Kotlin prefers to model properties through getters/setters but still puts annotations on the field. This simply is a recipe for disaster.

Anyway, I don’t know what changed in Hibernate 6 that changed the behavior, but we will look into this when we can.