diff --git a/lib/datadog/ci/configuration/components.rb b/lib/datadog/ci/configuration/components.rb
index 9abe9443..aafad49f 100644
--- a/lib/datadog/ci/configuration/components.rb
+++ b/lib/datadog/ci/configuration/components.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../flush"
 
 module Datadog
diff --git a/lib/datadog/ci/configuration/settings.rb b/lib/datadog/ci/configuration/settings.rb
index d75c5a77..fc3c38f9 100644
--- a/lib/datadog/ci/configuration/settings.rb
+++ b/lib/datadog/ci/configuration/settings.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../ext/settings"
 
 module Datadog
diff --git a/lib/datadog/ci/contrib/cucumber/configuration/settings.rb b/lib/datadog/ci/contrib/cucumber/configuration/settings.rb
index 9a0e6ccc..713094e6 100644
--- a/lib/datadog/ci/contrib/cucumber/configuration/settings.rb
+++ b/lib/datadog/ci/contrib/cucumber/configuration/settings.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../ext"
 
 require "datadog/tracing/contrib/configuration/settings"
diff --git a/lib/datadog/ci/contrib/cucumber/ext.rb b/lib/datadog/ci/contrib/cucumber/ext.rb
index 75fc21b4..4878a445 100644
--- a/lib/datadog/ci/contrib/cucumber/ext.rb
+++ b/lib/datadog/ci/contrib/cucumber/ext.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Contrib
@@ -5,14 +7,14 @@ module Cucumber
         # Cucumber integration constants
         # TODO: mark as `@public_api` when GA, to protect from resource and tag name changes.
         module Ext
-          APP = "cucumber".freeze
-          ENV_ENABLED = "DD_TRACE_CUCUMBER_ENABLED".freeze
-          ENV_OPERATION_NAME = "DD_TRACE_CUCUMBER_OPERATION_NAME".freeze
-          FRAMEWORK = "cucumber".freeze
-          OPERATION_NAME = "cucumber.test".freeze
-          SERVICE_NAME = "cucumber".freeze
-          STEP_SPAN_TYPE = "step".freeze
-          TEST_TYPE = "test".freeze
+          APP = "cucumber"
+          ENV_ENABLED = "DD_TRACE_CUCUMBER_ENABLED"
+          ENV_OPERATION_NAME = "DD_TRACE_CUCUMBER_OPERATION_NAME"
+          FRAMEWORK = "cucumber"
+          OPERATION_NAME = "cucumber.test"
+          SERVICE_NAME = "cucumber"
+          STEP_SPAN_TYPE = "step"
+          TEST_TYPE = "test"
         end
       end
     end
diff --git a/lib/datadog/ci/contrib/cucumber/formatter.rb b/lib/datadog/ci/contrib/cucumber/formatter.rb
index 239ae902..150218ac 100644
--- a/lib/datadog/ci/contrib/cucumber/formatter.rb
+++ b/lib/datadog/ci/contrib/cucumber/formatter.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../../test"
 require_relative "../../ext/app_types"
 require_relative "../../ext/environment"
diff --git a/lib/datadog/ci/contrib/cucumber/instrumentation.rb b/lib/datadog/ci/contrib/cucumber/instrumentation.rb
index 87688ddf..9e98cc58 100644
--- a/lib/datadog/ci/contrib/cucumber/instrumentation.rb
+++ b/lib/datadog/ci/contrib/cucumber/instrumentation.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "formatter"
 
 module Datadog
diff --git a/lib/datadog/ci/contrib/cucumber/integration.rb b/lib/datadog/ci/contrib/cucumber/integration.rb
index 2e9c4b2d..115ba47a 100644
--- a/lib/datadog/ci/contrib/cucumber/integration.rb
+++ b/lib/datadog/ci/contrib/cucumber/integration.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "configuration/settings"
 require_relative "patcher"
 
diff --git a/lib/datadog/ci/contrib/cucumber/patcher.rb b/lib/datadog/ci/contrib/cucumber/patcher.rb
index 9e1430da..268404bf 100644
--- a/lib/datadog/ci/contrib/cucumber/patcher.rb
+++ b/lib/datadog/ci/contrib/cucumber/patcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "datadog/tracing/contrib/patcher"
 require_relative "instrumentation"
 
diff --git a/lib/datadog/ci/contrib/minitest/configuration/settings.rb b/lib/datadog/ci/contrib/minitest/configuration/settings.rb
index 1ac6cd54..f412978e 100644
--- a/lib/datadog/ci/contrib/minitest/configuration/settings.rb
+++ b/lib/datadog/ci/contrib/minitest/configuration/settings.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../ext"
 
 require "datadog/tracing/contrib/configuration/settings"
diff --git a/lib/datadog/ci/contrib/minitest/ext.rb b/lib/datadog/ci/contrib/minitest/ext.rb
index 0ffaf746..b45ab2a3 100644
--- a/lib/datadog/ci/contrib/minitest/ext.rb
+++ b/lib/datadog/ci/contrib/minitest/ext.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Contrib
diff --git a/lib/datadog/ci/contrib/minitest/hooks.rb b/lib/datadog/ci/contrib/minitest/hooks.rb
index d8bba439..0bb61195 100644
--- a/lib/datadog/ci/contrib/minitest/hooks.rb
+++ b/lib/datadog/ci/contrib/minitest/hooks.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Contrib
diff --git a/lib/datadog/ci/contrib/minitest/integration.rb b/lib/datadog/ci/contrib/minitest/integration.rb
index 4be1ae1c..e918e25e 100644
--- a/lib/datadog/ci/contrib/minitest/integration.rb
+++ b/lib/datadog/ci/contrib/minitest/integration.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "configuration/settings"
 require_relative "patcher"
 
diff --git a/lib/datadog/ci/contrib/rspec/configuration/settings.rb b/lib/datadog/ci/contrib/rspec/configuration/settings.rb
index 2ece8d0c..c573b9e5 100644
--- a/lib/datadog/ci/contrib/rspec/configuration/settings.rb
+++ b/lib/datadog/ci/contrib/rspec/configuration/settings.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../ext"
 
 require "datadog/tracing/contrib/configuration/settings"
diff --git a/lib/datadog/ci/contrib/rspec/example.rb b/lib/datadog/ci/contrib/rspec/example.rb
index 7be45b27..e45e26c6 100644
--- a/lib/datadog/ci/contrib/rspec/example.rb
+++ b/lib/datadog/ci/contrib/rspec/example.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../../test"
 
 require_relative "../../ext/app_types"
diff --git a/lib/datadog/ci/contrib/rspec/ext.rb b/lib/datadog/ci/contrib/rspec/ext.rb
index 65351fac..9ce6ae1a 100644
--- a/lib/datadog/ci/contrib/rspec/ext.rb
+++ b/lib/datadog/ci/contrib/rspec/ext.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Contrib
@@ -5,13 +7,13 @@ module RSpec
         # RSpec integration constants
         # TODO: mark as `@public_api` when GA, to protect from resource and tag name changes.
         module Ext
-          APP = "rspec".freeze
-          ENV_ENABLED = "DD_TRACE_RSPEC_ENABLED".freeze
-          ENV_OPERATION_NAME = "DD_TRACE_RSPEC_OPERATION_NAME".freeze
-          FRAMEWORK = "rspec".freeze
-          OPERATION_NAME = "rspec.example".freeze
-          SERVICE_NAME = "rspec".freeze
-          TEST_TYPE = "test".freeze
+          APP = "rspec"
+          ENV_ENABLED = "DD_TRACE_RSPEC_ENABLED"
+          ENV_OPERATION_NAME = "DD_TRACE_RSPEC_OPERATION_NAME"
+          FRAMEWORK = "rspec"
+          OPERATION_NAME = "rspec.example"
+          SERVICE_NAME = "rspec"
+          TEST_TYPE = "test"
         end
       end
     end
diff --git a/lib/datadog/ci/contrib/rspec/integration.rb b/lib/datadog/ci/contrib/rspec/integration.rb
index 5ce19878..2121c50e 100644
--- a/lib/datadog/ci/contrib/rspec/integration.rb
+++ b/lib/datadog/ci/contrib/rspec/integration.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "datadog/tracing/contrib/integration"
 
 require_relative "configuration/settings"
diff --git a/lib/datadog/ci/contrib/rspec/patcher.rb b/lib/datadog/ci/contrib/rspec/patcher.rb
index 0dc057b6..80365e67 100644
--- a/lib/datadog/ci/contrib/rspec/patcher.rb
+++ b/lib/datadog/ci/contrib/rspec/patcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "datadog/tracing/contrib/patcher"
 require_relative "example"
 
diff --git a/lib/datadog/ci/ext/app_types.rb b/lib/datadog/ci/ext/app_types.rb
index 297e78a1..e83ad3c3 100644
--- a/lib/datadog/ci/ext/app_types.rb
+++ b/lib/datadog/ci/ext/app_types.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Ext
       module AppTypes
-        TYPE_TEST = "test".freeze
+        TYPE_TEST = "test"
       end
     end
   end
diff --git a/lib/datadog/ci/ext/environment/providers/base.rb b/lib/datadog/ci/ext/environment/providers/base.rb
index 77d1682c..82d2b514 100644
--- a/lib/datadog/ci/ext/environment/providers/base.rb
+++ b/lib/datadog/ci/ext/environment/providers/base.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Ext
diff --git a/lib/datadog/ci/ext/settings.rb b/lib/datadog/ci/ext/settings.rb
index c9424739..d74dbbd6 100644
--- a/lib/datadog/ci/ext/settings.rb
+++ b/lib/datadog/ci/ext/settings.rb
@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Ext
       # Defines constants for test tags
       module Settings
-        ENV_MODE_ENABLED = "DD_TRACE_CI_ENABLED".freeze
+        ENV_MODE_ENABLED = "DD_TRACE_CI_ENABLED"
       end
     end
   end
diff --git a/lib/datadog/ci/ext/test.rb b/lib/datadog/ci/ext/test.rb
index 8d4a0471..af7199fb 100644
--- a/lib/datadog/ci/ext/test.rb
+++ b/lib/datadog/ci/ext/test.rb
@@ -1,33 +1,35 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Ext
       # Defines constants for test tags
       module Test
-        CONTEXT_ORIGIN = "ciapp-test".freeze
+        CONTEXT_ORIGIN = "ciapp-test"
 
-        TAG_ARGUMENTS = "test.arguments".freeze
-        TAG_FRAMEWORK = "test.framework".freeze
-        TAG_FRAMEWORK_VERSION = "test.framework_version".freeze
-        TAG_NAME = "test.name".freeze
-        TAG_SKIP_REASON = "test.skip_reason".freeze # DEV: Not populated yet
-        TAG_STATUS = "test.status".freeze
-        TAG_SUITE = "test.suite".freeze
-        TAG_TRAITS = "test.traits".freeze
-        TAG_TYPE = "test.type".freeze
+        TAG_ARGUMENTS = "test.arguments"
+        TAG_FRAMEWORK = "test.framework"
+        TAG_FRAMEWORK_VERSION = "test.framework_version"
+        TAG_NAME = "test.name"
+        TAG_SKIP_REASON = "test.skip_reason" # DEV: Not populated yet
+        TAG_STATUS = "test.status"
+        TAG_SUITE = "test.suite"
+        TAG_TRAITS = "test.traits"
+        TAG_TYPE = "test.type"
 
         # Environment runtime tags
-        TAG_OS_ARCHITECTURE = "os.architecture".freeze
-        TAG_OS_PLATFORM = "os.platform".freeze
-        TAG_RUNTIME_NAME = "runtime.name".freeze
-        TAG_RUNTIME_VERSION = "runtime.version".freeze
+        TAG_OS_ARCHITECTURE = "os.architecture"
+        TAG_OS_PLATFORM = "os.platform"
+        TAG_RUNTIME_NAME = "runtime.name"
+        TAG_RUNTIME_VERSION = "runtime.version"
 
         # TODO: is there a better place for SPAN_KIND?
-        TAG_SPAN_KIND = "span.kind".freeze
+        TAG_SPAN_KIND = "span.kind"
 
         module Status
-          PASS = "pass".freeze
-          FAIL = "fail".freeze
-          SKIP = "skip".freeze
+          PASS = "pass"
+          FAIL = "fail"
+          SKIP = "skip"
         end
       end
     end
diff --git a/lib/datadog/ci/extensions.rb b/lib/datadog/ci/extensions.rb
index e0ec9f28..7c0c1ec2 100644
--- a/lib/datadog/ci/extensions.rb
+++ b/lib/datadog/ci/extensions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "datadog/core/configuration/settings"
 require "datadog/core/configuration/components"
 
diff --git a/lib/datadog/ci/flush.rb b/lib/datadog/ci/flush.rb
index c3771404..5fabf41e 100644
--- a/lib/datadog/ci/flush.rb
+++ b/lib/datadog/ci/flush.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "datadog/tracing/metadata/ext"
 require "datadog/tracing/flush"
 
diff --git a/lib/datadog/ci/utils/git.rb b/lib/datadog/ci/utils/git.rb
index 0afe8c7a..4e674966 100644
--- a/lib/datadog/ci/utils/git.rb
+++ b/lib/datadog/ci/utils/git.rb
@@ -1,19 +1,19 @@
+# frozen_string_literal: true
+
 module Datadog
   module CI
     module Utils
       module Git
-        module_function
-
-        def normalize_ref(name)
-          return nil if name.nil?
+        def self.normalize_ref(ref)
+          return nil if ref.nil?
 
           refs = %r{^refs/(heads/)?}
           origin = %r{^origin/}
           tags = %r{^tags/}
-          name.gsub(refs, "").gsub(origin, "").gsub(tags, "")
+          ref.gsub(refs, "").gsub(origin, "").gsub(tags, "")
         end
 
-        def is_git_tag?(ref)
+        def self.is_git_tag?(ref)
           !ref.nil? && ref.include?("tags/")
         end
       end
diff --git a/spec/datadog/ci/utils/git_spec.rb b/spec/datadog/ci/utils/git_spec.rb
new file mode 100644
index 00000000..c17700c5
--- /dev/null
+++ b/spec/datadog/ci/utils/git_spec.rb
@@ -0,0 +1,49 @@
+RSpec.describe ::Datadog::CI::Utils::Git do
+  describe ".normalize_ref" do
+    subject { described_class.normalize_ref(ref) }
+
+    context "when input is nil" do
+      let(:ref) { nil }
+
+      it { is_expected.to be_nil }
+    end
+
+    context "when input is github ref" do
+      let(:ref) { "refs/heads/master" }
+
+      it "strips everything out except ref name" do
+        is_expected.to eq("master")
+      end
+    end
+
+    context "when input includes tags" do
+      let(:ref) { "refs/heads/tags/0.1.0" }
+
+      it "strips everything out except ref name" do
+        is_expected.to eq("0.1.0")
+      end
+    end
+  end
+
+  describe ".is_git_tag?" do
+    subject { described_class.is_git_tag?(ref) }
+
+    context "when input is nil" do
+      let(:ref) { nil }
+
+      it { is_expected.to be_falsey }
+    end
+
+    context "when input is a branch" do
+      let(:ref) { "refs/heads/master" }
+
+      it { is_expected.to be_falsey }
+    end
+
+    context "when input includes tags" do
+      let(:ref) { "refs/heads/tags/0.1.0" }
+
+      it { is_expected.to be_truthy }
+    end
+  end
+end