diff --git a/Gemfile.lock b/Gemfile.lock
index 435d130..9f0c8c6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -173,7 +173,7 @@ GEM
     multi_test (0.1.2)
     mysql2 (0.5.2)
     nenv (0.3.0)
-    nio4r (2.3.1)
+    nio4r (2.4.0)
     nokogiri (1.10.3)
       mini_portile2 (~> 2.4.0)
     notiffany (0.1.1)