diff --git a/apivore.gemspec b/apivore.gemspec
index 59fe318..d76eff9 100644
--- a/apivore.gemspec
+++ b/apivore.gemspec
@@ -18,12 +18,12 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'rspec', '~> 3'
   s.add_runtime_dependency 'rspec-expectations', '~> 3.1'
   s.add_runtime_dependency 'rspec-mocks', '~> 3.1'
-  s.add_runtime_dependency 'actionpack', '~> 4'
+  s.add_runtime_dependency 'actionpack', '>= 4', '< 6'
   s.add_runtime_dependency 'hashie', '~> 3.3'
   s.add_development_dependency 'pry', '~> 0'
   s.add_development_dependency 'rake', '~> 10.3'
   s.add_development_dependency 'rspec-rails', '~> 3'
-  s.add_development_dependency 'activesupport', '~> 4'
+  s.add_development_dependency 'activesupport', '>= 4', '< 6'
 
   if RUBY_VERSION >= '2.2.0'
     s.add_development_dependency 'test-unit', '~> 3'