anchor.diff:   :handler {:and [admin-access operator-access]}}
   ----
   
  -Even more, you want allow readwrite access to administrators and operators, and
  -readonly access to any authenticated user:
  +Even more, you want to only allow read-write access to administrators
  +and operators, and read-only access to any authenticated user:
   
   [source,clojure]
   ----
  
positive.code:     (response "Hello Anonymous")))
  ----
  
  .Middlware usage example
  [source,clojure]
  ----
  ;; Import middleware function and backend constructor
  
negative.code: ;; -> "bd5f7a0040430a73f4845bac8f980c6398b4baae8a22efcc22038be0f4dd9678"
  ----
  
  NOTE: The key parameter can be any type that implements the currently
  undocumented *buddy.core.keys/ISecretKey* protocol (buddy comes with
  default implementations for String and byte[])
  
  
  Advanced usage
  ^^^^^^^^^^^^^^
  
  Like the other hash functions, hmac is implemented using Clojure
  protocols and is implementated for: String, byte[], *File*, *URL*,
  *URI* and *InputStream*.
  
  
  .Make hmac of file
  