diff --git a/lib/zeitwerk/loader.rb b/lib/zeitwerk/loader.rb
index 91737f6a..8727b4fb 100644
--- a/lib/zeitwerk/loader.rb
+++ b/lib/zeitwerk/loader.rb
@@ -83,9 +83,9 @@ class Loader
     # has only scanned the top-level, `shadowed_files` does not have shadowed
     # files that may exist deep in the project tree yet.
     #
-    # @private
     # @sig Set[String]
     attr_reader :shadowed_files
+    internal :shadowed_files
 
     # @private
     # @sig Mutex
diff --git a/test/lib/zeitwerk/test_unload.rb b/test/lib/zeitwerk/test_unload.rb
index 8bf256a5..6859f4aa 100644
--- a/test/lib/zeitwerk/test_unload.rb
+++ b/test/lib/zeitwerk/test_unload.rb
@@ -152,9 +152,9 @@ def self.name
       loader.push_dir("b")
       loader.setup
 
-      assert !loader.shadowed_files.empty? # precondition
+      assert !loader.__shadowed_files.empty? # precondition
       loader.unload
-      assert loader.shadowed_files.empty?
+      assert loader.__shadowed_files.empty?
     end
   end