While it's easy to let engineers be engineers, it can payoff to take risks and push them outside of their comfort zone. Since Node.js has recently become the second most starred project on Github, it makes sense to highlight Paypal's switch to the budding technology, and the rewards that followed.
For the curious, Erik Toth, Engineering Manager at Paypal, gave a great talk on Node.js at Scale.
Two months in to the Java development, two engineers started working on the parallel node.js app. In early June they met at a crossroads, the applications had the same set of functionality; the node.js application, a smaller team with a two month delayed start, had quickly caught up. A few details stood out after we ran the test cases and both applications passed the same functional tests. The node.js app was: Built almost twice as fast with fewer people Written in 33% fewer lines of code Constructed with 40% fewer files