diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index df77b24..e3f879e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -25,7 +25,7 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Ruby ${{ matrix.ruby-version }}
         uses: ruby/setup-ruby@v1
         with:
diff --git a/Gemfile b/Gemfile
index fd0c4a0..072b256 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,7 +3,8 @@ source "https://rubygems.org"
 # Specify your gem's dependencies in lint_roller.gemspec
 gemspec
 
-gem "rake"
+gem "m"
 gem "minitest"
+gem "rake"
+gem "simplecov"
 gem "standard"
-gem "m"
diff --git a/Gemfile.lock b/Gemfile.lock
index a4102b1..a5b4c37 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,43 +7,59 @@ GEM
   remote: https://rubygems.org/
   specs:
     ast (2.4.2)
-    json (2.6.3)
+    docile (1.4.1)
+    json (2.8.1)
     language_server-protocol (3.17.0.3)
     m (1.6.1)
       method_source (>= 0.6.7)
       rake (>= 0.9.2.2)
     method_source (1.0.0)
     minitest (5.18.0)
-    parallel (1.22.1)
+    parallel (1.26.3)
     parser (3.3.6.0)
       ast (~> 2.4.1)
       racc
     racc (1.8.1)
     rainbow (3.1.1)
     rake (13.0.6)
-    regexp_parser (2.7.0)
-    rexml (3.2.5)
-    rubocop (1.48.1)
+    regexp_parser (2.9.2)
+    rexml (3.3.9)
+    rubocop (1.64.1)
       json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)
-      parser (>= 3.2.0.0)
+      parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.8, < 3.0)
       rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.26.0, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.28.0)
-      parser (>= 3.2.1.0)
-    rubocop-performance (1.16.0)
-      rubocop (>= 1.7.0, < 2.0)
-      rubocop-ast (>= 0.4.0)
+    rubocop-ast (1.34.1)
+      parser (>= 3.3.1.0)
+    rubocop-performance (1.21.1)
+      rubocop (>= 1.48.1, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
     ruby-progressbar (1.13.0)
-    standard (1.26.0)
+    simplecov (0.22.0)
+      docile (~> 1.1)
+      simplecov-html (~> 0.11)
+      simplecov_json_formatter (~> 0.1)
+    simplecov-html (0.13.1)
+    simplecov_json_formatter (0.1.4)
+    standard (1.37.0)
       language_server-protocol (~> 3.17.0.2)
-      rubocop (~> 1.48.1)
-      rubocop-performance (~> 1.16.0)
-    unicode-display_width (2.4.2)
+      lint_roller (~> 1.0)
+      rubocop (~> 1.64.0)
+      standard-custom (~> 1.0.0)
+      standard-performance (~> 1.4)
+    standard-custom (1.0.2)
+      lint_roller (~> 1.0)
+      rubocop (~> 1.50)
+    standard-performance (1.4.0)
+      lint_roller (~> 1.1)
+      rubocop-performance (~> 1.21.0)
+    unicode-display_width (2.6.0)
 
 PLATFORMS
   arm64-darwin-22
@@ -55,6 +71,7 @@ DEPENDENCIES
   m
   minitest
   rake
+  simplecov
   standard
 
 BUNDLED WITH
diff --git a/test/lib/plugin_test.rb b/test/lib/plugin_test.rb
index 566f62f..cd0bb2c 100644
--- a/test/lib/plugin_test.rb
+++ b/test/lib/plugin_test.rb
@@ -65,7 +65,7 @@ def test_sample_roller
       ), SampleRoller.new.rules(Context.new)
       assert_equal Rules.new(
         error: Error.new("Unexpected Boom")
-      ), SampleRoller.new({💥: true}).rules(Context.new)
+      ), SampleRoller.new({:💥 => true}).rules(Context.new)
     end
   end
 end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index f71841c..3100a1b 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -1,4 +1,12 @@
 $LOAD_PATH.unshift File.expand_path("../lib", __dir__)
+begin
+  require "simplecov"
+  SimpleCov.start do
+    load_profile "test_frameworks"
+  end
+rescue LoadError
+end
+
 require "lint_roller"
 
 require "minitest/autorun"