anchor.diff:  
   == Project Maturity
   
  -Since _cats_ is a young project, there can be some link:api/index.html#id[API] breakage.
  +_cats_ already reached the 1.0.0 version and the link:api/index.html#id[API] is settled.
   
   
   == Install
  
positive.code: As we can see in the example below, the return of the `maybe-state` monad creates a stateful
  function that yields a Maybe containing a pair (value, next state).
  
  You probably noticed that we had to wrap the state function invocation with `cats.core/with-monad`.
  When working with monad transformers, we have to be explicit about what monad we are using to implement
  the binding policy since there is no way to distinguish values from a transformer type from those of
  a regular monad.
  
negative.code: ----
  (ns transformers.example
    (:require [cats.core :as m]
              [cats.context :as ctx]
              [cats.monad.maybe :as maybe]
              [cats.labs.state :as state]))
  
  (def maybe-state
    (state/state-transformer maybe/context))
  
  (ctx/with-context maybe-state
    (state/run-state (m/return 42) {}))
  ;; => #<Just #<Pair [42 {}]>>
  ----
  