diff --git a/CHANGELOG.md b/CHANGELOG.md
index 07b492b84a..e08c9dd70c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 # Haml Changelog
 
+* Add erubis to gemspec so that `benchmark.rb` works [#964](https://github.com/haml/haml/pull/964) (thanks [Dillon Welch](https://github.com/oniofchaos))
+
 ## 5.0.4
 
 Released on October 13, 2017
diff --git a/haml.gemspec b/haml.gemspec
index 7b0580cf39..78ff09b40b 100644
--- a/haml.gemspec
+++ b/haml.gemspec
@@ -22,6 +22,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'temple', '>= 0.8.0'
   spec.add_dependency 'tilt'
 
+  spec.add_development_dependency 'erubis' # for benchmark.rb
   spec.add_development_dependency 'rails', '>= 4.0.0'
   spec.add_development_dependency 'rbench'
   spec.add_development_dependency 'minitest', '>= 4.0'