diff --git a/killbill_client.gemspec b/killbill_client.gemspec
index f764fa4..016e689 100644
--- a/killbill_client.gemspec
+++ b/killbill_client.gemspec
@@ -39,11 +39,7 @@ Gem::Specification.new do |s|
 
   s.rdoc_options << '--exclude' << '.'
 
-  if RUBY_VERSION < '2.0.0'
-    s.add_dependency 'json', '>= 1.2.0', '< 2.0.0'
-  end
-
   s.add_development_dependency 'gem-release', '~> 2.2'
-  s.add_development_dependency 'rake', '>= 10.0.0', '< 11.0.0'
+  s.add_development_dependency 'rake', '~> 13.0'
   s.add_development_dependency 'rspec', '~> 3.4'
 end