Yes! There are 3 different “types” of Lemmy backends in our infrastructure. “scheduled” types, of which there can only be one, run scheduled federation traffic as well as some smaller load balanced load of requests. The “external” type handles generic requests same as “scheduled” except without scheduled federation tasks. These can spin up or down all the way to 0, as sometimes the scheduled instance can handle everything on its own.
Finally, there is “internal”. These are dedicated backend instances that are not publicly exposed and therefore do not handle any federation traffic at all. Lemmy-ui communicates with this internal backend, meaning that our UI has a path that is entirely separate to the federation traffic and should stay responsive no matter what!