anchor.diff:  ----
   (def trusted-algs #{:pbkdf2+sha256 :bcrypt+sha512})
   
  -(hashers/check incoming-pwd encrypted-pwd {:limit trusted-algs})
  +(hashers/check incoming-pwd derived-pwd {:limit trusted-algs})
   ----
   
   The `check` function will return false if the incoming password uses an algorithm
  
positive.code: [source, clojure]
  ----
  (letfn [(setter [pwd]
            (let [pwd (hashers/encrypt pwd)]
              (do-the-db-update pwd)))]
    (hashers/check incoming-pwd encrypted-pwd {:setter setter}))
  ----
  
  The setter will be called when the incoming password is valid but its config
  
negative.code: 
  
  === Rehash Hook
  
  Choice a strong algorithm is important thing, but have a good update
  password-hashes policy is also very important and usually completelly forgotten.
  