Quantcast is -- a huge amount of hadoop and performance sensitive code, and the majority of our external website. 1 - we self host 2 - the relevant performanc

Quantcast is -- a huge amount of hadoop and performance sensitive code, and the majority of our external website. 1 - we self host 2 - the relevant performance issue when using java to develop web apps is it's slower to build. I'd be pretty surprised if there were many cases where java / tomcat is slower to execute than rails or django. Now obviously all three are smoked by cached pages, but since a lot of our data needs to be updated daily, that isn't the easiest design for us.