diff --git a/simple-feed.gemspec b/simple-feed.gemspec
index 1dc5eda..19edf00 100644
--- a/simple-feed.gemspec
+++ b/simple-feed.gemspec
@@ -28,7 +28,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'awesome_print'
   spec.add_dependency 'base62-rb'
   spec.add_dependency 'colored2'
-  spec.add_dependency 'connection_pool', '~> 2'
+  spec.add_dependency 'connection_pool', '>= 2', '< 4'
   spec.add_dependency 'hashie'
   spec.add_dependency 'redis'
   spec.add_dependency 'sorted_set'