diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 49aa9b6b6..e1cf8d7ef 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -13,7 +13,7 @@ jobs:
 
     strategy:
       matrix:
-        ruby: ['3.1', '3.2', '3.3']
+        ruby: ['3.1', '3.2', '3.3', '3.4']
         db: ['postgresql', 'mysql2', 'sqlite3']
       fail-fast: false
 
diff --git a/Gemfile b/Gemfile
index 2385d5ef0..d5ad66002 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
-ruby '>= 3.1.0', '< 3.4.0'
+ruby '>= 3.1.0', '< 3.5.0'
 
 gem 'rails', '7.2.2.1'
 gem 'rouge', '~> 4.5'
diff --git a/doc/INSTALL b/doc/INSTALL
index 89c85479d..116a84468 100644
--- a/doc/INSTALL
+++ b/doc/INSTALL
@@ -7,7 +7,7 @@ https://www.redmine.org/
 
 == Requirements
 
-* Ruby 3.1, 3.2, 3.3
+* Ruby 3.1, 3.2, 3.3, 3.4
 
 * A database:
   * MySQL (tested with MySQL 8)
@@ -67,10 +67,10 @@ The current version of Firefox, Safari, Chrome, Chromium and Microsoft Edge.
 
    using:
      bundle exec rake assets:precompile RAILS_ENV="production"
-    
+
    If deploying to a sub-uri, set the relative URL root as follows:
      bundle exec rake assets:precompile RAILS_ENV="production" RAILS_RELATIVE_URL_ROOT=/sub-uri
-  
+
    If you experience issues with missing assets in the browser, try
    removing the public/assets directory before re-running the precompile:
      bundle exec rake assets:clobber RAILS_ENV="production"