On the JVM space, for rapid prototyping this study[1] found the most adequate to be Vaadin, Grails and GWT. Personally, I prefer Play with Scala. I think it's f

On the JVM space, for rapid prototyping this study[1] found the most adequate to be Vaadin, Grails and GWT. Personally, I prefer Play with Scala. I think it's fast enough for prototyping and can scale up beautifully both in application complexity and in load. But, I believe the answer is that the "best" language/framework is the one you know better and are most proficient in. [1] http://zeroturnaround.com/rebellabs/the-2014-decision-makers-guide-to-java-web-frameworks/11/ http://zeroturnaround.com/rebellabs/the-2014-decision-makers...