diff --git a/pkgs/os-specific/darwin/apple-source-releases/ICU/default.nix b/pkgs/os-specific/darwin/apple-source-releases/ICU/default.nix
index eef26f4b79a..6cf7ee07b70 100644
--- a/pkgs/os-specific/darwin/apple-source-releases/ICU/default.nix
+++ b/pkgs/os-specific/darwin/apple-source-releases/ICU/default.nix
@@ -20,5 +20,6 @@ appleDerivation {
 
   postInstall = ''
     mv $out/usr/local/include $out/include
+    rm -rf $out/usr
   '';
 }