Clojurians Log v2

Are there ClojureScript architectures that foster a pristine-pure functional programming model? The way I see it (which admittedly is a subjective definition of FP) is that one would be able to program with referentially-transparent, simple functions and data structures, without any sort of magic/reactive 'context' passed as a parameter (or much less, global state). Such a defn could as well be coded in .cljc with little to no differences between runtime branches. The framework would be plugged in at the edges of the application, instead of being something pervasive (and therefore difficult to swap). With these constraints, one would get specific benefits, e.g. being able to run 95% of your tests in any clojure runtime, very quickly (no IO involved). Or generatively test edge cases like ajax timeouts.