gemfileを変更 group :development, :test do gem 'guard' gem 'guard-livereload', '~> 2.5', require: false gem 'rack-livereload' end Guardfileを初期化、実行テスト $ bundle install $ guard init $ guard init livereload $ guard rack-livereloadを有効化(Rackのミドルウェアでスクリプトタグを本文に挿入して貰う) Rails.application.configure do ~ # Add Rack::LiveReload to the bottom of the middleware stack with the default options: config.middleware.insert_after ActionDispatch::Static, Rack::LiveReload # config.middleware.insert_before Rack::Lock, Rack::LiveReload # or, if you're using better_errors: # config.middleware.use(Rack::LiveReload, # min_delay : 500, # default 1000 # max_delay : 10_000, # default 60_000 # live_reload_port : 56789, # default 35729 # host : 'myhost.cool.wow', # ignore : [ %r{dont/modify\.html$} ] # ) ~ end 手動でスクリプト挿入でも良い <script src="http://hostname:35729/livereload.js?snipver=1"></script> guard 起動 $ bin/rails s $ gaurd ブラウザで接続する 拡張機能のアイコンをクリックして真ん中が引かれば接続成功 ※ポインタを合わせてしばらく待って[livereload connect]表示の確認でもよい - guard consoleにconnectedと表示されればok 参考 guard/guard-livereload: Guard::LiveReload automatically reload your browser when 'view' files are modified. johnbintz/rack-livereload: Bring in livereload.js into handy Rack middleware