diff --git a/Gemfile b/Gemfile
index ed0593f..84af0fb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,7 +4,7 @@ gem 'sass', '~> 3.2.12'
 gem 'bourbon', '~> 3.2.3'
 gem 'nanoc', '~> 3.6.5'
 gem 'multi_json', '~> 1.8.0'
-gem 'activesupport', '~> 4.0.0', require: 'active_support/all'
+gem 'activesupport', '~> 6.1.7', require: 'active_support/all'
 
 gem 'guard-nanoc', '~> 1.0.0'
 gem 'terminal-notifier-guard', '~> 1.5.3'
diff --git a/Gemfile.lock b/Gemfile.lock
index e7b3515..66b30fe 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,20 +1,20 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (4.0.0)
-      i18n (~> 0.6, >= 0.6.4)
-      minitest (~> 4.2)
-      multi_json (~> 1.3)
-      thread_safe (~> 0.1)
-      tzinfo (~> 0.3.37)
+    activesupport (6.1.7.1)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+      zeitwerk (~> 2.3)
     adsf (1.1.1)
       rack (>= 1.0.0)
-    atomic (1.1.14)
     bourbon (3.2.3)
       sass (~> 3.2)
       thor
     coderay (1.0.9)
     colored (1.2)
+    concurrent-ruby (1.1.10)
     cri (2.4.0)
       colored (>= 1.2)
     ffi (1.9.0)
@@ -28,14 +28,15 @@ GEM
     guard-nanoc (1.0.1)
       guard (>= 1.8.0)
       nanoc (>= 3.6.3)
-    i18n (0.6.5)
+    i18n (1.12.0)
+      concurrent-ruby (~> 1.0)
     listen (1.3.1)
       rb-fsevent (>= 0.9.3)
       rb-inotify (>= 0.9)
       rb-kqueue (>= 0.2)
     lumberjack (1.0.4)
     method_source (0.8.2)
-    minitest (4.7.5)
+    minitest (5.17.0)
     multi_json (1.8.1)
     nanoc (3.6.5)
       cri (~> 2.3)
@@ -53,15 +54,15 @@ GEM
     slop (3.4.6)
     terminal-notifier-guard (1.5.3)
     thor (0.18.1)
-    thread_safe (0.1.3)
-      atomic
-    tzinfo (0.3.38)
+    tzinfo (2.0.5)
+      concurrent-ruby (~> 1.0)
+    zeitwerk (2.6.6)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
-  activesupport (~> 4.0.0)
+  activesupport (~> 6.1.7)
   adsf (~> 1.1.1)
   bourbon (~> 3.2.3)
   guard-nanoc (~> 1.0.0)