What advantages have you found in creating a new namespace for it? We're creating a new namespace to have just one class, so my guess is that we can keep the previous approach, but maybe I'm missing something.

I agree that once we have only one class there is no need to create a new namespace. Removed it.

We also need to at least make the constructor private. If we want this to be even better singleton, we could also delete copy constructor and assignment operator.

Make it private, makes sense.

Shouldn't we use atomic also here?

Good catch! Std::atomic supports long long type, we can use it!
I've added it.

It looks like we don't need to specify the whole namespace here

Right! Made it shorter.

We agreed that we will keep capitalized names for methods generated by grpc, but it looks like RunServer and RunAmqpClient are defined by us and shouldn't be capitalized

We had comments about these functions before and agreed with you and @karol-bisztyga to use the same in all services. Now we have RunServer in other services. But I think we must switch to lower case in some follow-up diff for all server implementation in all services.

We're inside comm::network, so we don't need to specify the namespace

Thanks, fixed it.

I think that all the function names should start with lowercase except the ones generated by grpc. I don't think this is important to fix it now though.

Yes, but it needs to be updated in all services in main.cpp.