Add env ribbon on your rack application views.
$ gem install rack-env_ribbonAdd use Rack::EnvRibbon on your config.ru file.
require 'rack/env_ribbon'
app # => your rack application object
use Rack::EnvRibbon
run appAdd use Rack::EnvRibbon in the same way as rack application
require 'sinatra'
require 'rack/env_ribbon'
use Rack::EnvRibbon
get '/' do
<<~HTML
<!doctype html>
<html lang="ja">
<head>
<meta charset="utf-8">
<title>sinatra app</title>
</head>
<body>
<p>app body</p>
</body>
</html>
HTML
endAdd this line to your application's Gemfile
gem 'rack-env_ribbon'And then execute
$ bundleThe gem is available as open source under the terms of the MIT License.