“Build me a user-authentication system in two weeks” is a common phrase among R&D teams these days. For various reasons, this task has always been one of those things left for a single developer in the team to sort out. On one hand, you really don’t want to waste a lot of time doing it. On the other, you’re concerned that this kind of information might be better off handled by your own internally-written service, for better scaling later on. As new tutorials app