I find my self writing a lot of event.getSubject() in guard expressions. Wouldn't it be a good option to add this to the expression context in https://github.com/GlobalTradingTechnologies/workflow-extensions-bundle/blob/5266c0c9b35bb3867c383bcfb0e4caedfa804f20/Guard/ExpressionGuard.php#L123 Every GuardEvent has a subject. This would make my expressions a bit more readable.