Actually, Doppio is an artifact from my own research, so there is a very good reason &quot;why&quot; [0]! Basically, if you want to re-use your existing, well-tested code in the browser, it is quite difficult. The browser environment is very different from the environment that most programs expect. Doppio bridges the gap between the environment that these programs expect and the environment that the browser presents, making it possible to bring a full JVM into the browser that can run complicated, unmodified programs.<p>[0] Doppio: Breaking the Browser Language Barrier paper from PLDI 2014: <a href="https:&#x2F;&#x2F;plasma-umass.github.io&#x2F;doppio-demo&#x2F;paper.pdf" rel="nofollow">https:&#x2F;&#x2F;plasma-umass.github.io&#x2F;doppio-demo&#x2F;paper.pdf</a>