diff --git a/.github/workflows/require_relative_dir.yml b/.github/workflows/require_relative_dir.yml
index 352cad4..34b1523 100644
--- a/.github/workflows/require_relative_dir.yml
+++ b/.github/workflows/require_relative_dir.yml
@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu ]
-        ruby: [ 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, '3.0', head ]
+        ruby: [ 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, '3.0', 3.1, 3.2, head ]
         usage: [ modern, legacy ]
     steps:
       - name: checkout
diff --git a/lib/require_relative_dir.rb b/lib/require_relative_dir.rb
index 1b40b6b..f830769 100644
--- a/lib/require_relative_dir.rb
+++ b/lib/require_relative_dir.rb
@@ -16,7 +16,11 @@ def require_relative_dir(dir_name = SAME_AS_CALLER_NAME, except: nil, first: nil
   end
 
   refine Object do
-    include RequireRelativeDir
+    if respond_to?(:import_methods, true)
+      import_methods RequireRelativeDir
+    else
+      include RequireRelativeDir
+    end
     private :require_relative_dir
   end