hi - i want to use this in a rails 3 application. I've installed the gem but am uncertain where within my application to put the config block ( use Rack::Cors do ... end)? Documentation on this would be very helpful. Thank you!
Have a look at Rack Middleware section of the Rails Guides. If you're using Devise, be sure to put Cors before Warden.
The README seems to describe this clearly now, perhaps this issue can be closed.
Admittedly, the README isn't great, but I think it does cover this topic now. Please open a new issue if there are still gaps (with details).