Chef makes it so easy to change configuration en masse that it can be dangerous if not used with certain precautions and in accordance with a well thought out testing workflow. In our use of Chef at Etsy, we have devised many in-house best practices in response to failures which have helped greatly in avoiding catastrophic outages. This talk will focus on mistakes we've made and how we've avoided repeating them by enforcing standards in cookbooks, testing changes before rollout through the use of environments and in conjunction with the Spork plugin for Knife, and linting cookbooks with Foodcritic. I'll also talk about using handlers intelligently to monitor Chef runs and how to generate reports from the myriad data available in CouchDB.
