diff --git a/.github/workflows/danger.yml b/.github/workflows/danger.yml
index 5e99cbf53..12372470c 100644
--- a/.github/workflows/danger.yml
+++ b/.github/workflows/danger.yml
@@ -12,7 +12,7 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 2.7
+        ruby-version: 3.4
         bundler-cache: true
     - name: Run Danger
       run: |
diff --git a/.github/workflows/edge.yml b/.github/workflows/edge.yml
index c9d26044d..c73a44ad3 100644
--- a/.github/workflows/edge.yml
+++ b/.github/workflows/edge.yml
@@ -6,7 +6,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ['2.7', '3.0', '3.1', '3.2', '3.3', ruby-head, truffleruby-head, jruby-head]
+        ruby: ['2.7', '3.0', '3.1', '3.2', '3.3', '3.4', ruby-head, truffleruby-head, jruby-head]
         gemfile: [rails_edge, rack_edge]
         exclude:
           - ruby: '2.7'
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a7710f2aa..14a663818 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -12,7 +12,7 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 3.3
+        ruby-version: 3.4
         bundler-cache: true
         rubygems: latest
 
@@ -23,7 +23,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ['2.7', '3.0', '3.1', '3.2', '3.3']
+        ruby: ['2.7', '3.0', '3.1', '3.2', '3.3', '3.4']
         gemfile: [Gemfile, gemfiles/rack_2_0.gemfile, gemfiles/rack_3_0.gemfile, gemfiles/rack_3_1.gemfile, gemfiles/rails_6_1.gemfile, gemfiles/rails_7_0.gemfile, gemfiles/rails_7_1.gemfile, gemfiles/rails_7_2.gemfile, gemfiles/rails_8_0.gemfile]
         specs: ['spec --exclude-pattern=spec/integration/**/*_spec.rb']
         include:
diff --git a/spec/grape/api_spec.rb b/spec/grape/api_spec.rb
index bd6398780..20193ccb3 100644
--- a/spec/grape/api_spec.rb
+++ b/spec/grape/api_spec.rb
@@ -2970,9 +2970,10 @@ def self.call(object, _env)
           subject.put :yaml do
             params[:tag]
           end
-          put '/yaml', '<tag type="symbol">a123</tag>', 'CONTENT_TYPE' => 'application/xml'
+          body = '<tag type="symbol">a123</tag>'
+          put '/yaml', body, 'CONTENT_TYPE' => 'application/xml'
           expect(last_response).to be_successful
-          expect(last_response.body).to eql '{"type"=>"symbol", "__content__"=>"a123"}'
+          expect(last_response.body).to eq(Grape::Xml.parse(body)['tag'].to_s)
         end
       end
     end
diff --git a/spec/grape/endpoint_spec.rb b/spec/grape/endpoint_spec.rb
index f51e58213..0674731fe 100644
--- a/spec/grape/endpoint_spec.rb
+++ b/spec/grape/endpoint_spec.rb
@@ -391,14 +391,16 @@ def app
           expect(last_response.body).to eq('Bobby T.')
         end
       else
+        let(:body) { '<user>Bobby T.</user>' }
+
         it 'converts XML bodies to params' do
-          post '/request_body', '<user>Bobby T.</user>', 'CONTENT_TYPE' => 'application/xml'
-          expect(last_response.body).to eq('{"__content__"=>"Bobby T."}')
+          post '/request_body', body, 'CONTENT_TYPE' => 'application/xml'
+          expect(last_response.body).to eq(Grape::Xml.parse(body)['user'].to_s)
         end
 
         it 'converts XML bodies to params' do
-          put '/request_body', '<user>Bobby T.</user>', 'CONTENT_TYPE' => 'application/xml'
-          expect(last_response.body).to eq('{"__content__"=>"Bobby T."}')
+          put '/request_body', body, 'CONTENT_TYPE' => 'application/xml'
+          expect(last_response.body).to eq(Grape::Xml.parse(body)['user'].to_s)
         end
       end
 
@@ -685,7 +687,8 @@ def app
         if Gem::Version.new(RUBY_VERSION).release <= Gem::Version.new('3.2')
           %r{undefined local variable or method `undefined_helper' for #<Class:0x[0-9a-fA-F]+> in '/hey' endpoint}
         else
-          /undefined local variable or method `undefined_helper' for/
+          opening_quote = Gem::Version.new(RUBY_VERSION).release >= Gem::Version.new('3.4') ? "'" : '`'
+          /undefined local variable or method #{opening_quote}undefined_helper' for/
         end
       end
 
diff --git a/spec/grape/middleware/exception_spec.rb b/spec/grape/middleware/exception_spec.rb
index b3fe18144..b209b726f 100644
--- a/spec/grape/middleware/exception_spec.rb
+++ b/spec/grape/middleware/exception_spec.rb
@@ -220,7 +220,8 @@ def call(_env)
 
     it 'is possible to specify a custom formatter' do
       get '/'
-      expect(last_response.body).to eq('{:custom_formatter=&gt;&quot;rain!&quot;}')
+      response = Rack::Utils.escape_html({ custom_formatter: 'rain!' }.inspect)
+      expect(last_response.body).to eq(response)
     end
   end