def build
      @builder = Rack::Builder.new

      @middlewares.each do |middleware|
        if middleware[0] == :map
          @builder.map(middleware[1], &middleware[2])
        else
          @builder.use(*middleware[0], &middleware[1])
        end
      end

      @builder.run(@app)
    end
def build
      @builder = Rack::Builder.new

      @middlewares.each do |middleware|
        if middleware[0] == :map
          @builder.map(middleware[1], &middleware[2])
        else
          @builder.use(*middleware[0], &middleware[1])
        end
      end

      @builder.run(@app)
    end
Builds a new Rack::Builder with the middleware and the app