anchor.diff:     value. All requests with `:identity` key with nil value are considered not authenticated.
   3. User handler is called.
   
  +
   [NOTE]
   =========================
   - `parse` function can return valid response, in that case response is returned inmediatel
  
positive.code: --------------
  
  [[how-it-works]]
  How It Works
  ~~~~~~~~~~~~
  
  Each backend implements two protocols: `IAuthentication` and `IAuthorization`.
  
  
negative.code: - Modular Authentication library.
  - Modular Authorization library.
  - Regex/decorator based composable access rules system.
  - Password hashing library.
  - Signing library.
  - Crypto library.
  
  link:api/index.html[API reference documentation.]
  
  