diff --git a/Gemfile.lock b/Gemfile.lock
index 4fabc36..8509f74 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -36,10 +36,12 @@ GEM
     net-scp (1.2.1)
       net-ssh (>= 2.6.5)
     net-ssh (3.0.1)
+    nio4r (2.5.8)
     parallel (1.17.0)
     parser (2.6.3.0)
       ast (~> 2.4.0)
-    puma (3.11.4)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-flash3 (1.0.5)
       rack