diff --git a/test/custom_importer_test.rb b/test/custom_importer_test.rb
index 2375d1b..a978a26 100644
--- a/test/custom_importer_test.rb
+++ b/test/custom_importer_test.rb
@@ -3,7 +3,7 @@
 require_relative 'test_helper'
 
 module SassC
-  class CustomImporterTest < MiniTest::Test
+  class CustomImporterTest < Minitest::Test
     include TempFileTest
 
     class CustomImporter < Importer
diff --git a/test/engine_test.rb b/test/engine_test.rb
index cb93f83..20b7e76 100644
--- a/test/engine_test.rb
+++ b/test/engine_test.rb
@@ -3,7 +3,7 @@
 require_relative 'test_helper'
 
 module SassC
-  class EngineTest < MiniTest::Test
+  class EngineTest < Minitest::Test
     include TempFileTest
 
     def render(data)
diff --git a/test/error_test.rb b/test/error_test.rb
index a47005c..26c4e74 100644
--- a/test/error_test.rb
+++ b/test/error_test.rb
@@ -3,7 +3,7 @@
 require_relative 'test_helper'
 
 module SassC
-  class ErrorTest < MiniTest::Test
+  class ErrorTest < Minitest::Test
     def render(data, opts = {})
       Engine.new(data, opts).render
     end
diff --git a/test/functions_test.rb b/test/functions_test.rb
index 6405481..53e1830 100644
--- a/test/functions_test.rb
+++ b/test/functions_test.rb
@@ -4,7 +4,7 @@
 require 'stringio'
 
 module SassC
-  class FunctionsTest < MiniTest::Test
+  class FunctionsTest < Minitest::Test
     include FixtureHelper
 
     def setup
diff --git a/test/output_style_test.rb b/test/output_style_test.rb
index de334f1..4d40be1 100644
--- a/test/output_style_test.rb
+++ b/test/output_style_test.rb
@@ -3,7 +3,7 @@
 require_relative 'test_helper'
 
 module SassC
-  class OutputStyleTest < MiniTest::Test
+  class OutputStyleTest < Minitest::Test
     def input_scss
       <<~CSS
         $color: #fff;
diff --git a/test/vendor_test.rb b/test/vendor_test.rb
index 299fe23..c6bd661 100644
--- a/test/vendor_test.rb
+++ b/test/vendor_test.rb
@@ -3,7 +3,7 @@
 require_relative 'test_helper'
 
 module SassC
-  class VendorTest < MiniTest::Test
+  class VendorTest < Minitest::Test
     class PassthroughImporter < Importer
       def imports(path, _parent_path)
         Import.new(path)