As a software engineer for a company that generates analytics for advertisements, one technology that we leverage heavily is Node.js, which serves as a collection service for incoming status events when a user is watching a video. We had initially written the code that is doing this task a few years ago, when the newest stable version of Node.js was 0.10.18, and the “Express” module was in the 3.x branch. I’ve been looking to update our code to newer modules, and newer binaries, but updating doesn’t always mean a performance boost. I’ve read a lot about benchmarks comparing 0.10 and 0.12, and had seen people find 0.10 beating out the newer binaries, which fuels my caution about upgrading blindly into Node.js 4.1.0. Additionally, I have also been considering trying other web service modules, besides Express. Koa and Hapi have been getting attention, and I’ve seen benchmarking between all three, but I have yet to see a cross comparison with different versions of Node.js. I wanted to find out what branch of Node.js works the best with each module. Being that we have hundreds of Node.js processes behind load balancers, together handling 100s of million events per day, any minor change in performance could make a huge difference. If I’m going to make a change, I really want to be sure that it is a well informed one.