I can't comment on the technical parts of what you're offering as I don't know Rails, but it might be a good idea to use full sentences in your introductory tex

I can't comment on the technical parts of what you're offering as I don't know Rails, but it might be a good idea to use full sentences in your introductory text: "For example, deploying full rails environment to your server for your new app. Or as simple as installing and configuring iptables on your existing live server. "