diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 81c7841..4380a00 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -15,7 +15,7 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 3.0
+        ruby-version: 3.4
     - name: Install dependencies
       run: bundle install
     - name: Run RuboCop against BASE..HEAD changes
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index d529fce..8c57e01 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -5,18 +5,28 @@ on: [push]
 jobs:
   test:
     strategy:
+      fail-fast: false
       matrix:
         ruby-version:
           - '3.0'
           - '3.1'
           - '3.2'
           - '3.3'
+          - '3.4'
         gemfile:
           - gemfiles/Gemfile.rails61
           - gemfiles/Gemfile.rails70
           - gemfiles/Gemfile.rails71
           - gemfiles/Gemfile.rails72
+          - gemfiles/Gemfile.rails80
         exclude:
+          # rails 6.1 requires ruby < 3.4
+          - ruby-version: '3.4'
+            gemfile: 'gemfiles/Gemfile.rails61'
+          # rails 7.0 requires ruby >= 2.7, < 3.4
+          # https://www.fastruby.io/blog/ruby/rails/versions/compatibility-table.html
+          - ruby-version: '3.4'
+            gemfile: 'gemfiles/Gemfile.rails70'
           # rails 7.2 requires ruby >= 3.1
           # https://www.fastruby.io/blog/ruby/rails/versions/compatibility-table.html
           - ruby-version: '3.0'
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 631618a..c4e35d4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## [Unreleased]
-* no unreleased changes
+### Fixed
+* Support Ruby 3.4, Rails 8.0
 
 ## 2.4.2 / 2025-03-23
 * fix link with icon button style
diff --git a/gemfiles/Gemfile.rails80 b/gemfiles/Gemfile.rails80
new file mode 100644
index 0000000..4377f7d
--- /dev/null
+++ b/gemfiles/Gemfile.rails80
@@ -0,0 +1,5 @@
+source 'https://rubygems.org'
+
+gemspec path: '..'
+
+gem 'rails', '~> 8.0.0'
diff --git a/ndr_error.gemspec b/ndr_error.gemspec
index b50b5b5..ecc62c2 100644
--- a/ndr_error.gemspec
+++ b/ndr_error.gemspec
@@ -21,7 +21,7 @@ Gem::Specification.new do |s|
 
   s.required_ruby_version = '>= 3.0'
 
-  s.add_dependency 'rails', '>= 6.1', '< 7.3'
+  s.add_dependency 'rails', '>= 6.1', '< 8.1'
 
   # Support rails 6.1 with Ruby 3.1
   s.add_dependency 'net-imap'