Pretty good and much the same sensible architectural choices as many other already successful companies aside from the neo4j choice. Just use a normal db like postgres like everyone else. There are good reasons why the biggest sites in the world use or have moved to using an RDBMS. They may not be cool but they work. I'll not expand on all the reasons but a trivial search will enumerate them extensively. You already have some cool stuff like mongo, a store I love, and hate. ActiveMQ? I can't think of anyone else using it. Is there a good reason why everyone seems to be using rabbitmq?