You mean it's databases rather than what is in code? If so, then that's also news to me. I'd have thought that e.g. something like input validation code that c

You mean it's databases rather than what is in code? If so, then that's also news to me. I'd have thought that e.g. something like input validation code that can be reused both in backend and client would go under single source of truth. Which I would always prefer not to be repeated, but frequently hard to do unless you have same language in backend and frontend or codegen.