When I considered a real time communication protocol for our app I remember ruling out zeromq but I don't remember why... Maybe they don't offer an API as clean

When I considered a real time communication protocol for our app I remember ruling out zeromq but I don't remember why... Maybe they don't offer an API as clean/expressive? https://github.com/rsocket/rsocket/blob/master/Motivations.md https://github.com/rsocket/rsocket/blob/master/Motivations.m... Or was it backpressure? I wonder what are the pros of zeromq vs rsocket