rails sコマンド実行時に「Could not find a JavaScript runtime.」とエラーが出る場合の対処法 - ponkiti's blog$ rails s /home/vagrant/.rbenv/versions/2.0.0-p0/lib/ruby/gems/2.0.0/gems/execjs-2.2.2/lib/execjs/runtimes.rb:51:in `autodetect': Could not find a JavaScript runtime. See https://github.com/sstephenson/execjs for a list of available runtimes. (ExecJS::RuntimeUnavailable) from /home/vagrant/.rbenv/versions/2.0.0-p0/lib/ruby/gems/2.0.0/gems/execjs-2.2.2/lib/execjs.rb:5:in `<module:ExecJS>' （省略） from
