diff --git a/Gemfile b/Gemfile
index cccf6004f3..a1a19b9551 100644
--- a/Gemfile
+++ b/Gemfile
@@ -39,6 +39,7 @@ group :development do
 
   gem 'cocoapods-dependencies', '~> 1.0.beta.1'
 
+  gem 'activesupport', '>= 4.0.2', '< 5', '!= 4.2.11.12' # Pinned < 5 to ensure we're speccing 4.x.x
   gem 'bacon', :git => 'https://github.com/leahneukirchen/bacon.git'
   gem 'minitest', '5.12.0' # Pinned since > 5.12.0+ drops support for Ruby 2.0
   gem 'mocha'
diff --git a/Gemfile.lock b/Gemfile.lock
index 121eddd1b7..4441317b89 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -137,7 +137,7 @@ GEM
   remote: https://rubygems.org/
   specs:
     CFPropertyList (3.0.2)
-    activesupport (4.2.11.1)
+    activesupport (4.2.11.3)
       i18n (~> 0.7)
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
@@ -269,7 +269,7 @@ GEM
     tins (1.16.3)
     typhoeus (1.3.1)
       ethon (>= 0.9.0)
-    tzinfo (1.2.6)
+    tzinfo (1.2.7)
       thread_safe (~> 0.1)
     unicode-display_width (1.6.0)
     webmock (2.3.1)
@@ -282,6 +282,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  activesupport (>= 4.0.2, < 5, != 4.2.11.12)
   awesome_print
   bacon!
   bundler (~> 1.3)