I got an error below when I tried to run rails server after running rails new.
web_1 | /usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:80:in `rescue in block (2 levels) in require': There was an error while trying to load the gem 'uglifier'. (Bundler::GemRequireError)
All you need to do is the uncomment # gem 'therubyracer', platforms: :ruby in your Gemfile.
# See https://github.com/rails/execjs#readme for more supported runtimes
gem 'therubyracer', platforms: :ruby