diff --git a/Gemfile.lock b/Gemfile.lock
index e26e447..b9b1714 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -27,7 +27,7 @@ GEM
     ast (2.4.2)
     base64 (0.3.0)
     bigdecimal (4.1.2)
-    concurrent-ruby (1.3.6)
+    concurrent-ruby (1.3.7)
     connection_pool (2.5.5)
     coveralls (0.8.23)
       json (>= 1.8, < 3)