&quot;In their trial run, Julia was much faster than R. But I objected, because random walk is a sum. Thus one can generate the entire process in R as vector calls, one to generate the steps and then a call to cumsum(), e.g.&quot;<p>You missed the point. Everything is fast when you export what you&#x27;re doing to a library. Julia is fast when you do, and when you DON&#x27;T.