ExecJS and could not find a JavaScript runtime

Just add ExecJS and the Ruby Racer in your gem file and run bundle install after.

gem 'execjs'gem 'therubyracer'

Everything should be fine after.

ruby-on-rails-3.1 execjs javascript

Ubuntu Users

I'm on Ubuntu 11.04 and had similar issues. Installing Node.js fixed it.

As of Ubuntu 13.04 x64 you only need to run:

sudo apt-get install nodejs

This will solve the problem.

sudo yum install nodejs

ruby-on-rails-3.1 execjs javascript

In your Gem file, write

gem 'execjs'gem 'therubyracer'

and then run

bundle install

Everything works fine for me :)