> Configuration bugs are a disturbingly large portion of engineering decisions which cause outages I work in medical device software -- the stuff that runs on

> Configuration bugs are a disturbingly large portion of engineering decisions which cause outages I work in medical device software -- the stuff that runs on machines in hospital labs, ER's or at patient bedside. The first "ohmigod do we need to recall this?" bug I remember was an innocuous piece of code that was inserted to debug a specific problem, but which was supposed to be disabled in the "non-debug" configuration. Then somehow, the software update shipped with a change to the configuration file that enabled that code to run. Timing-critical debug code running on a real-time system with a hard deadline is a recipe for disaster. Thankfully, we got out of that pretty easily before it affected more than a small handful of users, but things could have been a lot worse.