anchor.diff:  ;; It will return a chunked response to the client with "HELLO WORLD" string.
   ----
   
  -Reactive streams implementation in link:http://ffff[futura library] comes with support for different
  -kind of coercions and with clojure 1.7 *transducers*.
  +Reactive streams implementation in link:https://github.com/funcool/futura[futura library] comes with
  +support for different kind of coercions and with clojure 1.7 *transducers*.
   
   
   == Websockets
  
positive.code: === Promises
  
  Promises is an other abstraction supported out of the box in _catacumba_. It comes from the
  link:http://fff[futura library] and is build on top of JDK8 _CompletableFuture_.
  
  Sometimes, yo do not need send a chunked stream to the clien, but your "bussines logic" is defined
  with asynchronous friendly api using promises (or something similar). In this case, with _catacumba_
  
negative.code:     (http/ok promise {:content-type "text/plain"})))
  ----
  
  Thanks to the *future* library internals, we can use it with 
  link:https://github.com/funcool/cats[cats] `mlet` macro, that allows us structure pure async 
  code in a synchronous way:
  
  [source, clojure]
  ----
  