wdym?

there is a global timeout handler or something like?

sorry I still don't get you. there are various things that can time out

I wanna say things like: if any handler last more then 3 seconds, call this other function

I'd create an interceptor that is present in every route In said interceptor, I'd plug in my concurrent facility of choice (java util.concurrent, clojure.core, core, async) to achieve the desired effect