diff --git a/Gemfile b/Gemfile
index 1b34f6f..8d96f54 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,4 +7,4 @@ gem "sass-embedded", "1.102.0" # avoids deprecation errors
 gem "just-the-docs", "0.12.0" # pinned to the current release
 # gem "just-the-docs"        # always download the latest release
 
-gem "psych", "~> 5.4.0" # needed for retire.rb, as the default is too old
+gem "psych", "~> 5.5.0" # needed for retire.rb, as the default is too old
diff --git a/Gemfile.lock b/Gemfile.lock
index 7310cc2..c1d6346 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -71,7 +71,7 @@ GEM
     mercenary (0.4.0)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    psych (5.4.0)
+    psych (5.5.0)
       date
       stringio
     public_suffix (7.0.5)
@@ -99,7 +99,7 @@ PLATFORMS
 DEPENDENCIES
   jekyll (~> 4.4.1)
   just-the-docs (= 0.12.0)
-  psych (~> 5.4.0)
+  psych (~> 5.5.0)
   sass-embedded (= 1.102.0)
 
 BUNDLED WITH