diff --git a/Library/Homebrew/extend/ENV/shared.rb b/Library/Homebrew/extend/ENV/shared.rb
index 3566a5c507d7bf0989f41554a63ce9008995e551..c253942ac6be48386e453651ea2819b00c739b02 100644
--- a/Library/Homebrew/extend/ENV/shared.rb
+++ b/Library/Homebrew/extend/ENV/shared.rb
@@ -329,3 +329,5 @@ module SharedEnvExtension
     version && Version.create(version) >= Version.create("4.8")
   end
 end
+
+require "extend/os/extend/ENV/shared"
diff --git a/Library/Homebrew/extend/os/extend/ENV/shared.rb b/Library/Homebrew/extend/os/extend/ENV/shared.rb
new file mode 100644
index 0000000000000000000000000000000000000000..676159b37a57f44380220d75efaaa265a759939f
--- /dev/null
+++ b/Library/Homebrew/extend/os/extend/ENV/shared.rb
@@ -0,0 +1,5 @@
+require "extend/ENV/shared"
+
+if OS.mac?
+  require "extend/os/mac/extend/ENV/shared"
+end
diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb b/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb
new file mode 100644
index 0000000000000000000000000000000000000000..7f81ffeb75372ced91c2c1d6af704c0b9dce568b
--- /dev/null
+++ b/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb
@@ -0,0 +1,2 @@
+module SharedEnvExtension
+end