diff --git a/test/lib/test_case.rb b/test/lib/test_case.rb
index 915aa14..33c28fb 100644
--- a/test/lib/test_case.rb
+++ b/test/lib/test_case.rb
@@ -5,7 +5,7 @@
 require 'rbconfig'
 
 module Open4
-  class TestCase < MiniTest::Unit::TestCase
+  class TestCase < Minitest::Test
     include Open4
 
     # Custom exception class for tests so we don't shadow possible