We have had problems but mainly with plugins. There&#x27;s basically no mandatory QA process for plugins, nor is there any facility to make it obvious to an updater that an upstream change affects a downstream plugin and might break it.<p>In my opinion, Jenkins is a product that you really need to have a test instance for, where you either have copies of your builds or you&#x27;ve set up some &#x27;unit test&#x27;-type builds to exercise functionality you depend on.