Example of a mini application using the Cuba framework (ruby) + HAML render engine + i18N

app.rb

require "cuba"
require "cuba/render"
require "tilt/haml"
require "sass"
require "i18n"
require "i18n/backend/fallbacks"

Cuba.plugin Cuba::Render

I18n::Backend::Simple.send(:include, I18n::Backend::Fallbacks)
I18n.load_path = Dir["./locales/*.yml"]
I18n.backend.load_translations
I18n.default_locale = :en

Cuba.settings[:render][:template_engine] = "haml"

Cuba.define do
  on "(en|es|pt|co|pe|br|cn)" do |locale|
    I18n.locale = locale
    on root do
      res.write partial("super_partial")
    end
  end

  on 'stylesheets', extension('css') do |file|
    on get do
      res['Content-Type'] = 'text/css'
      res.write render("assets/stylesheets/#{File.basename(file)}.scss")
    end
  end
end

Then, you can visit /en for the english version