This is very cool! I love the idea of having a structured way to incorporate tags and roles into DNS aliases.<p>However, since DNS is just about the most critical infrastructure service you can have, I want to point out that most of this can be accomplished nowadays with Route 53 internal DNS by syncing tags and roles into CNAMEs on Route 53.<p>The difference to me is that even if your syncing daemon goes down, your DNS is still up (it's hard to imagine a situation where Route 53 is down without something even more fundamental being down on EC2).