diff --git a/root.bp b/root.bp
index 95f089b1a..69933e8d6 100644
--- a/root.bp
+++ b/root.bp
@@ -15,6 +15,7 @@ optional_subdirs = [
     "frameworks/av",
     "frameworks/base",
     "frameworks/native",
+    "frameworks/wilhelm",
     "hardware/*",
     "libcore",
     "libnativehelper",