Thundr is a relatively new lightweight web framework for Java, adaptable for google app engine based applications development. It provides for a rich amount of services for working within the local platform as a service cloud environment especially in aspects of virtualized instances. There is aspects of easily modularizing components as well as a seamless approach towards API integration. One other interesting fact is that it does not utilize excessive levels of magic that are synonymous in many larger frameworks like SpringMVC or Grails. Such a framework would come in handy when applications are being deployed to the cloud, require good points of integration, are relatively lightweight, and do not get in way of one's desire for rapid application development.
