I use "real" in quotes to indicate I am meaning something other than the general meaning of the word "real". What I mean by this is a specific type of DI that I view as effective and a type of meta-programming. Such a DI system does more than just auto-instantiate objects. It also provides a DSL that allows for configuration and ordering of the object instantiation during different phases of system execution.

fx doesn't do that. It is primarily just a convenience way for tying things together in the single intended way. You can provide some configuration but it is not via a DSL; it is by making calls to the fx library.

Realistically to do the sort of DI I am referring to with Golang there would need to be a preprocessing step during compilation that generates Golang code.