Sure. I'm actually working on a bootstrap project which uses Gists and Node.js to spin up a scaling infrastructure: https://github.com/franklovecchio/yc-bootstrap. Instead of using CloudFormation, which I loathe, or Puppet/Chef (which have a learning curve and infrastructure for latter), I use standard bash libraries (see yc-bootstrap/gists/) and "extend" them to spin up instances -- see the README under "Gisting": (https://github.com/franklovecchio/yc-bootstrap/blob/master/R...). That example is what the user-data file would be.