// TODO: shouldn't this be a stack too? Then session attribute not needed
transientMapper = new GoalToJellyScriptHousingMapper();
// Create the Jelly session
Session session = new JellySession( baseContext.getXMLOutput() );
session.setAttribute( BASE_CONTEXT, baseContext );
session.setAttribute( PLUGIN_MANAGER, this );
session.setAttribute( GOAL_MAPPER, transientMapper );
// add the global session to the pluginContext so that it can be used by tags
baseContext.setVariable( GLOBAL_SESSION_KEY, session );
// Execution of the Jelly scripts: