diff --git a/idempotent-request.gemspec b/idempotent-request.gemspec
index 00094ac..69e99d4 100644
--- a/idempotent-request.gemspec
+++ b/idempotent-request.gemspec
@@ -23,7 +23,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'rack', '~> 2.0'
   spec.add_dependency 'oj', '~> 3.0'
 
-  spec.add_development_dependency 'bundler', '~> 1.15'
+  spec.add_development_dependency 'bundler'
   spec.add_development_dependency 'rake', '~> 10.0'
   spec.add_development_dependency 'rspec', '~> 3.0'
   spec.add_development_dependency 'fakeredis', '~> 0.6'