It's easy to have two implementations of your rate-limiting thing, in-process and Redis. Or change your implementation when you need it. Just put a nice interfa

It's easy to have two implementations of your rate-limiting thing, in-process and Redis. Or change your implementation when you need it. Just put a nice interface in front of it. There is a cost to the network synchronisation, so you definitely want to scale vertically until you really must scale horizontally.