Without more details about the project requirements, my initial impression is that the author could get most of these features from Zookeeper, which is designe

Without more details about the project requirements, my initial impression is that the author could get most of these features from Zookeeper, which is designed for stuff like distributed locks and synchronization. However I've seen the pattern to use the database for a complete system synchronization in multiple projects. Don't have to say how this is a bad thing - probably easy to start with but a nightmare to scale later, just like the author mentioned in the article.