diff --git a/.github/workflows/coverage.yaml b/.github/workflows/coverage.yaml
new file mode 100644
index 0000000..81f3c65
--- /dev/null
+++ b/.github/workflows/coverage.yaml
@@ -0,0 +1,57 @@
+name: Coverage
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+env:
+  CONSOLE_OUTPUT: XTerm
+  COVERAGE: PartialSummary
+
+jobs:
+  test:
+    name: ${{matrix.ruby}} on ${{matrix.os}}
+    runs-on: ${{matrix.os}}-latest
+    
+    strategy:
+      matrix:
+        os:
+          - ubuntu
+          - macos
+        
+        ruby:
+          - "3.2"
+    
+    steps:
+    - uses: actions/checkout@v3
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{matrix.ruby}}
+        bundler-cache: true
+    
+    - name: Run tests
+      timeout-minutes: 5
+      run: bundle exec bake test
+
+    - uses: actions/upload-artifact@v2
+      with:
+        name: coverage-${{matrix.os}}-${{matrix.ruby}}
+        path: .covered.db
+  
+  validate:
+    needs: test
+    runs-on: ubuntu-latest
+    
+    steps:
+    - uses: actions/checkout@v3
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: "3.2"
+        bundler-cache: true
+    
+    - uses: actions/download-artifact@v3
+    
+    - name: Validate coverage
+      timeout-minutes: 5
+      run: bundle exec bake covered:validate --paths */.covered.db \;
diff --git a/multipart-post.gemspec b/multipart-post.gemspec
index 525294f..e11dbd2 100644
--- a/multipart-post.gemspec
+++ b/multipart-post.gemspec
@@ -21,4 +21,5 @@ Gem::Specification.new do |spec|
 	
 	spec.add_development_dependency "bundler"
 	spec.add_development_dependency "rspec", "~> 3.4"
+	spec.add_development_dependency "covered"
 end
diff --git a/spec/multipart/post/parts_spec.rb b/spec/multipart/post/parts_spec.rb
index 0f4a189..bbd076f 100644
--- a/spec/multipart/post/parts_spec.rb
+++ b/spec/multipart/post/parts_spec.rb
@@ -77,6 +77,11 @@ def content_type; 'application/data'; end
         part = Parts::FilePart.new("boundary", "afile", UploadIO.new(TEMP_FILE, "text/plain"), { "Content-Type" => "application/pdf" })
         expect(part.to_io.read).to match(/Content-Type: application\/pdf/)
       end
+
+      it "test_content_id" do
+        part = Parts::FilePart.new("boundary", "afile", UploadIO.new(TEMP_FILE, "text/plain"), { "Content-ID" => "id" })
+        expect(part.to_io.read).to match(/Content-ID: id/)
+      end
     end
 
     RSpec.describe Parts::ParamPart do
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 4196306..78a7e55 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -4,25 +4,8 @@
 # Copyright, 2017-2022, by Samuel Williams.
 # Copyright, 2019, by Patrick Davey.
 
-if ENV['COVERAGE']
-	begin
-		require 'simplecov'
-		
-		SimpleCov.start do
-			add_filter "/spec/"
-		end
-		
-		if ENV['TRAVIS']
-			require 'coveralls'
-			Coveralls.wear!
-		end
-	rescue LoadError
-		warn "Could not load simplecov: #{$!}"
-	end
-end
-
 require "bundler/setup"
-require "multipart/post"
+require "covered/rspec"
 
 MULTIBYTE = File.join(__dir__, 'fixtures/multibyte.txt')
 TEMP_FILE = "temp.txt"