diff --git a/image_properties.h b/image_properties.h
index ac6d474..4f94eeb 100644
--- a/image_properties.h
+++ b/image_properties.h
@@ -45,6 +45,10 @@
   // the version, signing keys and build target.
   std::string build_fingerprint;
 
+  // The Android build type, should be either 'user', 'userdebug' or 'eng'.
+  // It's empty string on other platform.
+  std::string build_type;
+
   // The board name this image was built for.
   std::string board;