I'm not the hugest fan of coffeescript, but I don't know if you can consider it to be an 'exotic' language at this point. It's quite widely accepted.
Maybe saying it's widely accepted isn't entirely appropriate, but it certainly is gaining a lot of traction.
Once you are releasing things outside of your controlled/team environment using anything but JS is just a loop for others to jump through.
Considering that, releases would be in JS, as they should be.