Do you even gRPC/avro/thrift/IDL bro? I know those aren’t the data structures you probably meant, but those are data structures that are commonly shared. That

Do you even gRPC/avro/thrift/IDL bro? I know those aren’t the data structures you probably meant, but those are data structures that are commonly shared. That’s different than a model though, which I think is really what OP is talking about. There’s no problem in sharing a library but it is a model which works best with a monolith or a monorepo (and obviously one language). You definitely DO NOT want multiple versions of your library kicking around.