In order to get a general idea of how k6 is performing, and to see if there are any low-hanging fruit in terms of optimizations we could do, I did a series of tests running k6 against a local server, testing different changes to the k6 code base.
macOS High Sierra 10.13.13
MacBook Pro(Retina, 15-inch, Mid 2014)
Processor: 2,2Ghz Intel Core i7
Memory: 16GB 1600MHz DDR3