diff --git a/rescuetime.gemspec b/rescuetime.gemspec
index 7091679..6159786 100644
--- a/rescuetime.gemspec
+++ b/rescuetime.gemspec
@@ -22,7 +22,7 @@ Gem::Specification.new do |spec|
 
   spec.required_ruby_version = '>= 2.0.0', '< 2.6'
 
-  spec.add_development_dependency 'bundler', '~> 1.17.3'
+  spec.add_development_dependency 'bundler'
   spec.add_development_dependency 'rake', '>= 12.3.3'
 
   spec.add_development_dependency 'rspec', '~> 3.2', '>= 3.2.0'