"The example application proved nonetheless that building an application without middle tier, based on AngularJS + MongoDB, is possible and very straightforward

"The example application proved nonetheless that building an application without middle tier, based on AngularJS + MongoDB, is possible and very straightforward" Making the minimal featureset in the article happen seems like a necessary but not sufficient condition to demonstrate that this technique is "straightforward". Certainly, if implementing that app isn't straightforward then anything more complicated is doomed - but reading through the RESTHeart docs does not fill me with confidence that things of realistic complexity will be straightforward. For instance, the RESTHeart "security" layer offers your choice of two different not-remotely-production-ready "toy" identity managers; one that works from a file of usernames & passwords, and one that uses a Mongo collection of usernames and UNHASHED CLEARTEXT PASSWORDS. If you want something better? Well fire up the ol' Java IDE... I'd also quibble with the entire premise - RESTHeart _is_ a middle tier. It's one that depends on YAML configuration rather than boilerplate code to accomplish the features used in the article, but it's still a Java app that deploys separately from Mongo.