appcontrollersadmin_controller.rb

class AdminController < ApplicationController
  layout "admin"
  http_basic_authenticate_with :name => "user", :password => "password"
end

appcontrollersadmincoasters_controller.rb

class Admin::CoastersController < AdminController
  def index
  end

  def show
  end

  -- Other restful routes --
end

configroutes.rb

namespace :admin do
  resources :coasters # This one will hit Admin::CoastersController
end

resources :coasters   # This one will hit CoastersController (the one you already have)

root to: "pages#home"

Mike, Did you mean to alter the gist in some way? As far as I can see, it looks identical.

There we go, fixed.