The selling point of these referred frameworks is the time to market. Do it in a way we know it has worked for so many people so far, and the framework code glu

The selling point of these referred frameworks is the time to market. Do it in a way we know it has worked for so many people so far, and the framework code glues pieces together to make it good for you. Make it good for you until a particular reasonable scale. No framework can claim to be the best fit in all the several dimensions on which they can be measured, one of which is, "time to market", today of all time. At scale everything breaks down and need a custom implementation. If anything the framework needs to be good at, it is, how well it allows itself to be replaced and with how little effort. Twitter is gradually moving all it's components into the "best production platform" JVM today. I don't think any body can provide convincing argument that building it on JVM right from the beginning would have been a better solution. Outgrow a framework and roll your own at the points that are critical for your application. Do the common things like, sending emails etc, in a standard way and let it be handled the reasonably right way.