diff --git a/Gemfile b/Gemfile
index 844bf78..d2cc99f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -14,6 +14,6 @@ group :development do
   end
   group :test do
     gem 'rake', '~> 13.2.1'
-    gem 'minitest', '~> 5.22.2'
+    gem 'minitest', '~> 5.23.0'
   end
 end
diff --git a/Rakefile b/Rakefile
index d0be0af..f89e674 100644
--- a/Rakefile
+++ b/Rakefile
@@ -5,4 +5,9 @@ require 'minitest/test_task'
 # * test:isolated : run tests independently to surface order dependencies
 # * test:deps     : (alias of test:isolated)
 # * test:slow     : run tests and reports the slowest 25
-Minitest::TestTask.create
+Minitest::TestTask.create do |t|
+  t.extra_args << '-Werror' # Raise exceptions for warnings: https://github.com/minitest/minitest/commit/f0f17b9
+  if RUBY_VERSION > '3.3'
+    t.test_prelude = 'Warning[:performance] = true' # … including `performance` warnings which are off even with `-w`
+  end
+end