diff --git a/Gemfile.lock b/Gemfile.lock
index f246c40..6b93f56 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -26,7 +26,7 @@ GEM
     ast (2.4.3)
     base64 (0.3.0)
     bigdecimal (4.0.1)
-    concurrent-ruby (1.3.6)
+    concurrent-ruby (1.3.7)
     connection_pool (3.0.2)
     diff-lcs (1.5.0)
     drb (2.2.3)