All interfaces are service boundaries. The only difference is whether you controll all clients and servers or not. Either way, API versioning is a must and triv

All interfaces are service boundaries. The only difference is whether you controll all clients and servers or not. Either way, API versioning is a must and trivial to implement, and there is really no excuse to avoid it. All it takes is a single integration problem caused by versioning problemd to waste more time than it takes to implememt API versioning.