diff --git a/examples/simple_rails_api/Gemfile.lock b/examples/simple_rails_api/Gemfile.lock
index 4e78dc3..4f34439 100644
--- a/examples/simple_rails_api/Gemfile.lock
+++ b/examples/simple_rails_api/Gemfile.lock
@@ -64,7 +64,7 @@ GEM
       msgpack (~> 1.0)
     builder (3.3.0)
     byebug (11.1.3)
-    concurrent-ruby (1.3.4)
+    concurrent-ruby (1.3.7)
     crass (1.0.6)
     date (3.3.4)
     erubi (1.13.0)