diff --git a/Appraisals b/Appraisals
index 17dcf10..d0a82d8 100644
--- a/Appraisals
+++ b/Appraisals
@@ -49,4 +49,8 @@ end
 
 appraise 'nobrainer' do
   gem 'nobrainer'
+
+  # When activesupport 5 was released, it required ruby 2.2.2 as a minimum.
+  # Locking this down to 4.2.6 allows our Ruby 1.9 tests to keep working.
+  gem 'activesupport', '4.2.6', :platforms => :ruby_19
 end
diff --git a/gemfiles/nobrainer.gemfile b/gemfiles/nobrainer.gemfile
index 23b0ee5..ba4de3c 100644
--- a/gemfiles/nobrainer.gemfile
+++ b/gemfiles/nobrainer.gemfile
@@ -3,5 +3,6 @@
 source "https://rubygems.org"
 
 gem "nobrainer"
+gem "activesupport", "4.2.6", :platforms => :ruby_19
 
 gemspec :path => "../"