Accessing underscore.js on Heroku for local execution within Rails app -

I need to execute the user-generated JavaScript on Heroku under Rails and I underscores before running in my V8 context I want to load JJ. I have been using underscore-rail gem for user-base js browser-side execution purposes, so I want to draw an underscore.js file from my server gem store. My question is, how can I find this file in the gem store? Alternatively, is it a better way to handle it?

and then download and then whatever javascript files you use in underscores Want to, at the top

  var _ = ('underscore');   
 And in your business  
 The node can be easily placed in V8, and whatever you have to run it in Heroko.