I understand your desire to program defensively, and this would accomplish this for this routine.  If you want to add that enhancement to this routine, I'm fine w/ that.

I'm more interested in framing Chris' problem and tackling that head-on, and also figuring out a better code organization for the three use cases we seem to have:

1.  Satisfy Jenkins
1.  One line command application configuration (what `configure` presently accomplishes).
1.   One line deployment to personal servers (right now, Heroku) for users like Chris.

Until we have a handle on that, everything remains "suboptimal" in terms of configuration and reliability.