public final function initialiseModules()
    {
        foreach ($this->modules as $module) {
            $module->initialiseModule();
        }

        // Initialise the application 'module' itself.
        $this->initialiseModule();

        $handlers = [];
        foreach ($this->modules as $module) {
            $handlers[] = $module->getUrlHandlers();
        }

        $this->rootHandlers = $this->filterUrlHandlers($handlers);
    }