jReCo (JSF Rendering Controller, User authorizer) is a rule engine for JSF applications. It provides clear and simple way for managing rendering state of application components. jReCo lives in JSF application context. Based on defined rules it modifies the state of components. jReCo Rules use Java like syntax and are stored in separate files. From application point of view there is no need to write any rendering logic in Java or JSF code. All is taken care externally by jReCo. Using jReCo allows developers to separate rule based rendering logic from the rest of the application. It makes the application better structured and more readable. The rule definitions can be updated during application runtime without the need to restart the server. jReCo is extendable by registering Java methods within jReCo’s syntax.