Joining Container to Multiple Docker Networks

what is the ‘blessed by discourse’ method to use multiple docker networks? multiple --network invocations aren’t supported in docker run, so i don’t think i can specify multiple networks using docker_args.

i tunnel user requests to the edge via an --internal docker network, but having that as the only network causes launcher rebuild to fail since it needs internet. so i would want to have a wan network (i guess just for building?) and an internal tunnel network (real traffic).

do i really have to come up with something to docker network connect tunnel app after every build/start? can i have the discourse launcher do it?