I just used AMQP routing to handle loads, and small limited-run programs that cache credentials like netflix biological inspired systems. We were never convinced gRPC could efficiently handle the periodic traffic spike-nature of our data streams (more of n! edges in fault tolerant mode concern). i.e. we run our intake like an insect colony to handle the various architecture roles, and each process instance is only handling a few network links at a time (i.e. gets rid of threading cleanup, busy credential store hits, and error routing.)

I wish they used Erlang/Elixir/Phoenix channels to reduce the system complexity,

https://dev.to/codecast/how-to-use-phoenix-channels-18k9

Sometimes we just need to keep a system running, and quietly replace it with version 2 later... Yet later usually never arrives... lol =)