diff --git a/Gemfile.lock b/Gemfile.lock
index 254f817..801a0d7 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -235,6 +235,7 @@ GEM
     net-ssh (5.0.1)
     net-ssh-gateway (2.0.0)
       net-ssh (>= 4.0.0)
+    nio4r (2.5.8)
     nokogiri (1.10.5)
       mini_portile2 (~> 2.4.0)
     notiffany (0.1.1)
@@ -254,7 +255,8 @@ GEM
       method_source (~> 0.8)
       slop (~> 3.4)
     public_suffix (3.0.2)
-    puma (3.11.4)
+    puma (5.6.4)
+      nio4r (~> 2.0)
     rack (1.6.12)
     rack-contrib (1.8.0)
       rack (~> 1.4)