> Shared data structures? Common library? Services have an API. If you are sharing data structures and a common "core" library across services, yes, you are off

> Shared data structures? Common library? Services have an API. If you are sharing data structures and a common "core" library across services, yes, you are officially doing it wrong. From the architecture diagram it also looks like there's only one MongoDB instance, which, if you have multiple services talking to the same database[0], is also a major sign that you're doing it wrong. Yes, and that API has types, e.g. protocol buffers. And also, sometimes you just want to change the API, and you want to make that as easy as possible.