diff --git a/Gemfile.lock b/Gemfile.lock
index 36d7a54..53c5915 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -187,6 +187,7 @@ GEM
     net-scp (1.2.1)
       net-ssh (>= 2.6.5)
     net-ssh (2.9.2)
+    nio4r (2.5.9)
     nokogiri (1.6.6.2)
       mini_portile (~> 0.6.0)
     nokogumbo (1.2.0)
@@ -204,9 +205,9 @@ GEM
       nokogiri (~> 1.6.1)
       public_suffix (~> 1.1.3)
     public_suffix (1.1.3)
-    puma (2.11.1)
-      rack (>= 1.1, < 2.0)
-    rack (1.6.0)
+    puma (5.6.7)
+      nio4r (~> 2.0)
+    rack (1.6.13)
     rack-contrib (1.2.0)
       rack (>= 0.9.1)
     rack-cors (0.3.1)