diff --git a/examples/ruby_conf/Gemfile.lock b/examples/ruby_conf/Gemfile.lock
index e87419c..2984e2d 100644
--- a/examples/ruby_conf/Gemfile.lock
+++ b/examples/ruby_conf/Gemfile.lock
@@ -61,7 +61,8 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
-    puma (3.8.2)
+    puma (5.6.2)
+      nio4r (~> 2.0)
     rack (2.0.1)
     rb-readline (0.5.4)
     slop (3.6.0)