diff --git a/appraisal/ruby-3.4.rb b/appraisal/ruby-3.4.rb
index 4c0cf60bd99..43a4e1eb122 100644
--- a/appraisal/ruby-3.4.rb
+++ b/appraisal/ruby-3.4.rb
@@ -125,6 +125,9 @@
   gem 'sneakers', '>= 2.12.0'
   gem 'sucker_punch'
   gem 'que', '>= 1.0.0'
+
+  # When Rack 3+ is used, we need rackup.
+  gem 'rackup'
 end
 
 [
diff --git a/gemfiles/ruby_3.4_contrib.gemfile b/gemfiles/ruby_3.4_contrib.gemfile
index 3afda7b1380..aee3ff4df95 100644
--- a/gemfiles/ruby_3.4_contrib.gemfile
+++ b/gemfiles/ruby_3.4_contrib.gemfile
@@ -43,6 +43,7 @@ gem "sidekiq", "~> 7"
 gem "sneakers", ">= 2.12.0"
 gem "sucker_punch"
 gem "que", ">= 1.0.0"
+gem "rackup"
 
 group :check do
   gem "ruby_memcheck", ">= 3"
diff --git a/gemfiles/ruby_3.4_contrib.gemfile.lock b/gemfiles/ruby_3.4_contrib.gemfile.lock
index d17af5081a1..5054b7d3ce3 100644
--- a/gemfiles/ruby_3.4_contrib.gemfile.lock
+++ b/gemfiles/ruby_3.4_contrib.gemfile.lock
@@ -113,6 +113,8 @@ GEM
       rack (>= 3.0.0)
     rack-test (2.1.0)
       rack (>= 1.3)
+    rackup (2.2.0)
+      rack (>= 3)
     rainbow (3.1.1)
     rake (12.3.3)
     rake-compiler (1.2.7)
@@ -247,6 +249,7 @@ DEPENDENCIES
   pry-stack_explorer
   que (>= 1.0.0)
   rack-test
+  rackup
   rake (>= 12.3)
   rake-compiler (~> 1.1, >= 1.1.1)
   resque
diff --git a/spec/datadog/tracing/contrib/suite/integration_spec.rb b/spec/datadog/tracing/contrib/suite/integration_spec.rb
index b6279e74baf..eaf37eb1f8a 100644
--- a/spec/datadog/tracing/contrib/suite/integration_spec.rb
+++ b/spec/datadog/tracing/contrib/suite/integration_spec.rb
@@ -8,7 +8,7 @@
 
 require 'rack'
 # `Rack::Handler::WEBrick` was extracted to the `rackup` gem in Rack 3.0
-require 'rackup' if Rack::VERSION[0] >= 3
+require 'rackup' if Gem::Version.new(Rack::RELEASE) >= Gem::Version.new('3')
 require 'webrick'
 
 RSpec.describe 'contrib integration testing', :integration do