diff --git a/jekyll-seo-tag.gemspec b/jekyll-seo-tag.gemspec
index 75abd13..5d06090 100644
--- a/jekyll-seo-tag.gemspec
+++ b/jekyll-seo-tag.gemspec
@@ -27,9 +27,9 @@ Gem::Specification.new do |spec|
   spec.require_paths = ["lib"]
 
   spec.add_dependency "jekyll", "~> 3.3"
-  spec.add_development_dependency "bundler", "~> 1.10"
-  spec.add_development_dependency "rake", "~> 10.0"
-  spec.add_development_dependency "rspec", "~> 3.3"
-  spec.add_development_dependency "html-proofer", "~> 2.5"
+  spec.add_development_dependency "bundler", "~> 1.14"
+  spec.add_development_dependency "rake", "~> 12.0"
+  spec.add_development_dependency "rspec", "~> 3.5"
+  spec.add_development_dependency "html-proofer", "~> 3.6"
   spec.add_development_dependency "rubocop", "~> 0.48"
 end
diff --git a/spec/jekyll_seo_tag_spec.rb b/spec/jekyll_seo_tag_spec.rb
index e2bcb0b..47ca794 100755
--- a/spec/jekyll_seo_tag_spec.rb
+++ b/spec/jekyll_seo_tag_spec.rb
@@ -31,7 +31,7 @@ describe Jekyll::SeoTag do
       :check_html       => true,
       :checks_to_ignore => %w(ScriptCheck LinkCheck ImageCheck),
     }
-    status = HTML::Proofer.new(dest_dir, options).run
+    status = HTMLProofer.check_directory(dest_dir, options).run
     expect(status).to eql(true)
   end
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index a68ada5..bbb2756 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,7 +1,7 @@
 $LOAD_PATH.unshift File.expand_path("../../lib", __FILE__)
 require "jekyll"
 require "jekyll-seo-tag"
-require "html/proofer"
+require "html-proofer"
 
 ENV["JEKYLL_LOG_LEVEL"] = "error"