Scheduled EBS snapshots

As part of my Ghost setup on AWS, I wanted to make sure I had backups of EBS in case things go wrong (as they always do, eventually). I couldn't find many guides for this, surprisingly. I guess most people use the AWS UI for this, or haven't published their solutions, or trust EBS and what they change on it more than they should.

I did find something pretty close to what I wanted, a blog post on How to Schedule Daily Rolling EBS Snapshots. I expanded on this and made it a github repo for everyone to use. Thanks to the original author for the help here, and I hope others are helped out by my additions here.