diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index b3779c2..e37a7bf 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -13,7 +13,7 @@ jobs:
         rails: [61, 70, 71, 72]
 
         # Rails 7.2 requires ruby 3.1 and higher
-        # Rails 8.0 requires ruby 3.2 and higher
+        # Rails 8.0/8.1 requires ruby 3.2 and higher
         include:
           - ruby: "3.0"
             rails: 61
@@ -25,11 +25,19 @@ jobs:
             rails: 80
           - ruby: "3.3"
             rails: 80
+          - ruby: "3.4"
+            rails: 80
+          - ruby: "3.2"
+            rails: 81
+          - ruby: "3.3"
+            rails: 81
+          - ruby: "3.4"
+            rails: 81
     env:
       BUNDLE_GEMFILE: gemfiles/rails_${{ matrix.rails }}.gemfile
     steps:
       - name: checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: setup Ruby
         uses: ruby/setup-ruby@v1
         with:
diff --git a/Appraisals b/Appraisals
index 5700240..300437b 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,11 +1,13 @@
 appraise 'rails-61' do
   gem 'activerecord', '~> 6.1.0'
   gem 'actionpack',   '~> 6.1.0'
+  gem 'concurrent-ruby', '< 1.3.5' # as https://github.com/rails/rails/pull/49372 was never backported
 end
 
 appraise 'rails-70' do
   gem 'activerecord', '~> 7.0.0'
   gem 'actionpack',   '~> 7.0.0'
+  gem 'concurrent-ruby', '< 1.3.5' # as https://github.com/rails/rails/pull/49372 was never backported
 end
 
 appraise 'rails-71' do
@@ -25,3 +27,11 @@ appraise 'rails-80' do
     gem 'sqlite3', '~> 2.1'
   end
 end
+
+appraise 'rails-81' do
+  gem 'activerecord', '~> 8.1.0'
+  gem 'actionpack',   '~> 8.1.0'
+  platforms :ruby do
+    gem 'sqlite3', '~> 2.1'
+  end
+end
diff --git a/Rakefile b/Rakefile
index 67476cd..21c90c1 100644
--- a/Rakefile
+++ b/Rakefile
@@ -13,6 +13,7 @@ rails_versions = %w(
   7.1
   7.2
   8.0
+  8.1
 )
 
 rails_versions.each do |version|
diff --git a/default_value_for.gemspec b/default_value_for.gemspec
index f5a4a11..c1f9eab 100644
--- a/default_value_for.gemspec
+++ b/default_value_for.gemspec
@@ -14,9 +14,9 @@ Gem::Specification.new do |s|
     'lib/default_value_for.rb',
     'lib/default_value_for/railtie.rb'
   ]
-  s.add_dependency 'activerecord', '>= 6.1', '< 8.1'
-  s.add_development_dependency 'actionpack', '>= 6.1', '< 8.1'
-  s.add_development_dependency 'railties', '>= 6.1', '< 8.1'
+  s.add_dependency 'activerecord', '>= 6.1', '< 8.2'
+  s.add_development_dependency 'actionpack', '>= 6.1', '< 8.2'
+  s.add_development_dependency 'railties', '>= 6.1', '< 8.2'
   s.add_development_dependency 'minitest', '>= 5.0'
   s.add_development_dependency 'minitest-around'
   s.add_development_dependency 'appraisal'
diff --git a/gemfiles/rails_61.gemfile b/gemfiles/rails_61.gemfile
index f373744..4dea9ef 100644
--- a/gemfiles/rails_61.gemfile
+++ b/gemfiles/rails_61.gemfile
@@ -4,6 +4,7 @@ source "https://rubygems.org"
 
 gem "activerecord", "~> 6.1.0"
 gem "actionpack", "~> 6.1.0"
+gem "concurrent-ruby", "< 1.3.5"
 
 platforms :jruby do
   gem "activerecord-jdbcsqlite3-adapter", ">= 1.3", "< 61"
diff --git a/gemfiles/rails_70.gemfile b/gemfiles/rails_70.gemfile
index 6aeae0e..06ab1ba 100644
--- a/gemfiles/rails_70.gemfile
+++ b/gemfiles/rails_70.gemfile
@@ -4,6 +4,7 @@ source "https://rubygems.org"
 
 gem "activerecord", "~> 7.0.0"
 gem "actionpack", "~> 7.0.0"
+gem "concurrent-ruby", "< 1.3.5"
 
 platforms :jruby do
   gem "activerecord-jdbcsqlite3-adapter", ">= 1.3", "< 61"
diff --git a/gemfiles/rails_81.gemfile b/gemfiles/rails_81.gemfile
new file mode 100644
index 0000000..b43a2be
--- /dev/null
+++ b/gemfiles/rails_81.gemfile
@@ -0,0 +1,17 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "activerecord", "~> 8.1.0"
+gem "actionpack", "~> 8.1.0"
+
+platforms :jruby do
+  gem "activerecord-jdbcsqlite3-adapter", ">= 1.3", "< 61"
+  gem "jruby-openssl", "~> 0.9.4"
+end
+
+platforms :ruby do
+  gem "sqlite3", "~> 2.1"
+end
+
+gemspec path: "../"