I have a class that is used to be serialized to Json without problems with kotlin 1.2 (0.6.2 with no customized serializers). after migrating to 1.3 (0.8,3), it stopped working, complaining about either some enum class or java singletonMap can't be serialized. is this expected? I don't see any mentioning about backward imcompatibility in the 1.3 doc.

I don’t think it’s expected, can you please file more detailed issue with code to reproduce on the github?

thanks for the response! i couldn't post detail about my production code, but i'll try to create a minimal example.