Refuse to use Protobufs, or getting gray waiting for kotlinx serialization official support. I present github.com/chrisjenx/serialkompat Mimics compat/checks for backwards and forwards compatiblity against your DTO's on and off KMP projects you can check if those pesky DTO changes will break your deployed apps! Gradle Task that can baseline and then fail if dangerous changes are made - add to you CI, why write tests when tooling should do the work for you! If you find edge cases or bugs, let me know. Already live on a very large project.