diff --git a/lib/allure-ruby-adaptor-api/builder.rb b/lib/allure-ruby-adaptor-api/builder.rb
index dd0241d..8eb62cc 100644
--- a/lib/allure-ruby-adaptor-api/builder.rb
+++ b/lib/allure-ruby-adaptor-api/builder.rb
@@ -123,7 +123,7 @@ def build!(opts = {}, &block)
         suites_xml = []
         (self.suites || []).each do |suite_title, suite|
           builder = Nokogiri::XML::Builder.new do |xml|
-            xml.send "ns2:test-suite", :start => suite[:start] || 0, :stop => suite[:stop] || 0, 'xmlns' => '', "xmlns:ns2" => "urn:model.allure.qatools.yandex.ru" do
+            xml['ns2'].send 'test-suite', :start => suite[:start] || 0, :stop => suite[:stop] || 0, 'xmlns' => '', 'xmlns:ns2' => 'urn:model.allure.qatools.yandex.ru' do
               xml.send :name, suite_title
               xml.send :title, suite_title
               xml.send "test-cases" do