Not if there isn't an interface. If I create one, sure, but then I would have to do that on all dev computers as well and I'd have to forward the address someho

Not if there isn't an interface. If I create one, sure, but then I would have to do that on all dev computers as well and I'd have to forward the address somehow into all server and client configs and/or command-lines of tools started as part of the build process. Just overriding "localhost" spares me from both (the address to resolve is provided as an env variable, just like LD_PRELOAD itself - and env variables are inherited by child processes, which is great in my scenario).