Jenkins's biggest strength is also its biggest weakness: plugins. Any development shop that has been using Jenkins for a while is using at least a bunch of plugins. Plugins are not stable, they break every now and then. They require constant update with new Jenkins versions. They get abandoned by their creators (hell, many plugins still don't support pipeline).
It's a fundamental issue with how Jenkins is set up that I don't know how they can get away with unless they abandon the whole plugin architecture all together. But obviously that's not a solution.
It's a fundamental issue with how Jenkins is set up that I don't know how they can get away with unless they abandon the whole plugin architecture all together. But obviously that's not a solution.