I suppose the answer to 1. is some combination of API versioning and unit testing. Cloud APIs aren't different from usual, local APIs in that respect. How do yo

I suppose the answer to 1. is some combination of API versioning and unit testing. Cloud APIs aren't different from usual, local APIs in that respect. How do you deal with breaking changes in libraries? Unit testing and using your IDE's capabilities to detect signature / protocol changes. As for 2. I'm not sure if there's a generally accepted best practice for this but again I think this isn't much different from more traditional scenarios. A workable approach probably is using migrations, i.e. the app checks via an API endpoint if there are new migrations (using a timestamp) and if there are downloads and applies those.