diff --git a/konacha.gemspec b/konacha.gemspec
index 5ce7470..803b21e 100644
--- a/konacha.gemspec
+++ b/konacha.gemspec
@@ -32,5 +32,6 @@ the asset pipeline and engines.}
   gem.add_development_dependency "coffee-script"
   gem.add_development_dependency "ejs"
   gem.add_development_dependency "tzinfo"
-  gem.add_development_dependency "poltergeist", "~> 1.0.3"
+  gem.add_development_dependency "selenium-webdriver"
+  gem.add_development_dependency "poltergeist", "~> 1.3.0"
 end
diff --git a/spec/runner_spec.rb b/spec/runner_spec.rb
index f235c56..7f8cdab 100644
--- a/spec/runner_spec.rb
+++ b/spec/runner_spec.rb
@@ -3,7 +3,6 @@
 describe Konacha::Runner do
   before do
     Konacha.mode = :runner
-    STDOUT.stub(:puts)
   end
 
   describe ".new" do
@@ -31,6 +30,7 @@
     before do
       Konacha.configure do |config|
         config.driver = driver
+        config.formatters = [Konacha::Formatter.new(StringIO.new)]
       end
     end