Repository Statistics in Raptor

We revisit an old topic: computing statistics over a repository. This time, we have a concrete example taken from the Raptor web framework, which has its own statistics script that results in very detailed plots. Along the way, we'll see some shell details, including some confusing behavior from the `time` builtin. Raptor's statistics script and the run-command-on-git-revisions script are both available if you'd like to try them out.