How do I use (n)curses in Ruby?

I'd like to create a progress bar to indicate the status of an a batch job in Ruby.

I've read some tutorials / libraries on using (n)curses, none of which were particularly helpful in explaining how to create an "animated" progress bar in the terminal or using curses with Ruby.

I'm already aware of using a separate thread to monitor the progress of a given job, I'm just not sure how to proceed with drawing a progress bar.