diff --git a/Gemfile b/Gemfile
index e4901223f95aac61da81df33c295b200b6bf72aa..9b1076baf87090dde15a55ca210b8b48225170b4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -488,7 +488,7 @@ gem 'flipper', '~> 0.21.0'
 gem 'flipper-active_record', '~> 0.21.0'
 gem 'flipper-active_support_cache_store', '~> 0.21.0'
 gem 'unleash', '~> 3.2.2'
-gem 'gitlab-experiment', '~> 0.6.2'
+gem 'gitlab-experiment', '~> 0.6.3'
 
 # Structured logging
 gem 'lograge', '~> 0.5'
diff --git a/Gemfile.lock b/Gemfile.lock
index 38dc22cd5661317d97cade3fce8a006462917481..999bed3eb4d38f0368661331da7a0e42357b75a1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -463,7 +463,7 @@ GEM
     gitlab-dangerfiles (2.3.0)
       danger (>= 8.3.1)
       danger-gitlab (>= 8.0.0)
-    gitlab-experiment (0.6.2)
+    gitlab-experiment (0.6.3)
       activesupport (>= 3.0)
       request_store (>= 1.0)
       scientist (~> 1.6, >= 1.6.0)
@@ -1468,7 +1468,7 @@ DEPENDENCIES
   github-markup (~> 1.7.0)
   gitlab-chronic (~> 0.10.5)
   gitlab-dangerfiles (~> 2.3.0)
-  gitlab-experiment (~> 0.6.2)
+  gitlab-experiment (~> 0.6.3)
   gitlab-fog-azure-rm (~> 1.1.1)
   gitlab-labkit (~> 0.21.0)
   gitlab-license (~> 2.0)
diff --git a/spec/experiments/application_experiment_spec.rb b/spec/experiments/application_experiment_spec.rb
index 4966e508f7e0a1b3f2a5e07c52c211971df310c0..b288d074133aec2f68f700d46048a53e2c1af218 100644
--- a/spec/experiments/application_experiment_spec.rb
+++ b/spec/experiments/application_experiment_spec.rb
@@ -236,6 +236,11 @@
         expect(subject.process_redirect_url(url)).to be_nil
       end
     end
+
+    it "generates the correct urls based on where the engine was mounted" do
+      url = Rails.application.routes.url_helpers.experiment_redirect_url(subject, url: 'https://docs.gitlab.com')
+      expect(url).to include("/-/experiment/namespaced%2Fstub:#{subject.context.key}?https://docs.gitlab.com")
+    end
   end
 
   context "when resolving variants" do
diff --git a/spec/experiments/new_project_readme_content_experiment_spec.rb b/spec/experiments/new_project_readme_content_experiment_spec.rb
index f76b8a1ded1857a78a7157df619b30365afc88f5..a6a81580a2951dde19fa5e5dfd905da52b5d2c7d 100644
--- a/spec/experiments/new_project_readme_content_experiment_spec.rb
+++ b/spec/experiments/new_project_readme_content_experiment_spec.rb
@@ -30,9 +30,9 @@
     end
 
     it "renders redirect URLs" do
-      expect(markdown).to include(
-        Rails.application.routes.url_helpers.experiment_redirect_url(subject, url: initial_url)
-      )
+      url = Rails.application.routes.url_helpers.experiment_redirect_url(subject, url: initial_url)
+      expect(url).to include("/-/experiment/#{subject.to_param}?")
+      expect(markdown).to include(url)
     end
   end
 end