I felt that rxjava has similar philosophy behind. Whether it is UI or interaction with an external API, -- declaring relations -- declaring transformation th

I felt that rxjava has similar philosophy behind. Whether it is UI or interaction with an external API, -- declaring relations -- declaring transformation that must occur on the data flowing through those relations -- instantiating by means of asynchronous observers appears, at least in my view, have similar concepts as rxJava (or other non-java implementations) Therefore, a question to others -- what are non-trivial differentiators between PLRelational and Rx<*> family of libraries?