diff --git a/Gemfile b/Gemfile
index 32514f0..b6d9cdc 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,6 +4,7 @@ source 'https://rubygems.org'
 
 gemspec
 
+gem 'rack', '>= 2.2.13'
 gem 'resque'
 
 group :development do
diff --git a/Gemfile.lock b/Gemfile.lock
index ec8007c..a200c00 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -17,7 +17,7 @@ GEM
     parser (3.2.0.0)
       ast (~> 2.4.1)
     power_assert (2.0.3)
-    rack (2.2.9)
+    rack (2.2.17)
     rack-protection (3.0.5)
       rack
     rainbow (3.1.1)
@@ -66,6 +66,7 @@ PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
+  rack (>= 2.2.13)
   rake
   resque
   resque-lock!