We worked hard to have a very accurate change log in https://github.com/wmde/WikibaseDataModel/blob/master/RELEASE-NOTES.md. Please make sure you are not using any of the functionality mentioned as a breaking change in 5.0 and 6.0. Being cross-compatible with all versions including 4.0 is fine then.
We worked hard to have a very accurate change log in https://github.com/wmde/WikibaseDataModel/blob/master/RELEASE-NOTES.md. Please make sure you are not using any of the functionality mentioned as a breaking change in 5.0 and 6.0. Being cross-compatible with all versions including 4.0 is fine then.