Show HN: Getting started with Ruby and Sinatra

The guide is alright, but it could be improved. I'd add/mention/change the following:

Installing Ruby on Windows: http://rubyinstaller.org/

Running `bundle install` is not a good idea, because it will install gems as root (and globally); unless you use bundler version >= 2, which isn't the stable release yet (it defaults to the behaviour in the next sentence). A better alternative is to use `bundle install --path .bundle`.

Another thing that's maybe worth mentioning that Sinatra has a "DSL" with lots of interesting settings, which can be changed using `set`, `enable`, `disable`, and mention how to access those settings using the `settings` object.

For example, an interesting settings that could be mentioned are `:port`, `:public_folder`, `:static`, and `:sessions`.

Also, perhaps you could link to the official website, if people want to look into more details of the guide.

A side note, and a design idea for the website (although it would require more effort overall) is to add "tabs" for Linux/Windows/OSX/etc operating systems. For this particular guide, there's not many differences (if any).

Really great work, J. Your guide goes into the right about of detail about getting Sinatra up and running, without any fluff, or 'humor'.

Title should read "getting started with Ruby and Sinatra."