diff --git a/Appraisals b/Appraisals
index e9d2e21..00b4bca 100644
--- a/Appraisals
+++ b/Appraisals
@@ -3,6 +3,11 @@ appraise "rack_2_0" do
 end
 
 appraise "rack_1_6" do
+  # Override activesupport and actionpack version constraints by making
+  # it more loose so it's compatible with rack 1.6.x
+  gem "actionpack", ">= 4.2"
+  gem "activesupport", ">= 4.2"
+
   gem "rack", "~> 1.6.9"
 
   # Override rack-test version constraint by making it more loose
diff --git a/gemfiles/rack_1_6.gemfile b/gemfiles/rack_1_6.gemfile
index 8b636ed..0cc0050 100644
--- a/gemfiles/rack_1_6.gemfile
+++ b/gemfiles/rack_1_6.gemfile
@@ -2,6 +2,8 @@
 
 source "https://rubygems.org"
 
+gem "actionpack", ">= 4.2"
+gem "activesupport", ">= 4.2"
 gem "rack", "~> 1.6.9"
 gem "rack-test", ">= 0.6"
 
diff --git a/rack-attack.gemspec b/rack-attack.gemspec
index d7fddc4..dd5e628 100644
--- a/rack-attack.gemspec
+++ b/rack-attack.gemspec
@@ -32,6 +32,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'rack', ">= 1.0", "< 3"
 
   s.add_development_dependency 'appraisal', '~> 2.2'
+  s.add_development_dependency "bundler", "~> 1.16"
   s.add_development_dependency 'minitest', "~> 5.11"
   s.add_development_dependency "minitest-stub-const", "~> 0.6"
   s.add_development_dependency 'rack-test', "~> 1.0"
@@ -46,6 +47,6 @@ Gem::Specification.new do |s|
 
   # The following are potential runtime dependencies users may have,
   # which rack-attack uses only for testing compatibility in test suite.
-  s.add_development_dependency 'actionpack', '>= 3.0.0'
-  s.add_development_dependency 'activesupport', '>= 3.0.0'
+  s.add_development_dependency 'actionpack', '~> 5.2'
+  s.add_development_dependency 'activesupport', '~> 5.2'
 end