diff --git a/examples/simple_rails_api/Gemfile.lock b/examples/simple_rails_api/Gemfile.lock
index 5aa3eb6..d9492fe 100644
--- a/examples/simple_rails_api/Gemfile.lock
+++ b/examples/simple_rails_api/Gemfile.lock
@@ -86,7 +86,7 @@ GEM
     mini_portile2 (2.5.0)
     minitest (5.14.2)
     msgpack (1.3.3)
-    nio4r (2.5.4)
+    nio4r (2.5.8)
     nokogiri (1.11.1)
       mini_portile2 (~> 2.5.0)
       racc (~> 1.4)
@@ -96,7 +96,7 @@ GEM
     pry-byebug (3.9.0)
       byebug (~> 11.0)
       pry (~> 0.13.0)
-    puma (4.3.6)
+    puma (4.3.9)
       nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)