diff --git a/vmpooler.gemspec b/vmpooler.gemspec
index f6fedeb..39127d3 100644
--- a/vmpooler.gemspec
+++ b/vmpooler.gemspec
@@ -45,7 +45,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'pry'
   s.add_development_dependency 'rack-test', '>= 0.6'
   s.add_development_dependency 'rspec', '>= 3.2'
-  s.add_development_dependency 'rubocop'
+  s.add_development_dependency 'rubocop', '< 1.0'
   s.add_development_dependency 'simplecov', '>= 0.11.2'
   s.add_development_dependency 'yarjuf', '>= 2.0'
 end