diff --git a/Gemfile.lock b/Gemfile.lock
index fdb369f..ab0f240 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -37,7 +37,7 @@ GEM
     multi_json (1.11.2)
     multipart-post (2.0.0)
     puma (3.0.2)
-    rack (1.6.4)
+    rack (2.1.1)
     rb-readline (0.5.3)
     redis (3.2.2)
     redis-namespace (1.5.2)