diff --git a/packages/rtl/types.pas b/packages/rtl/types.pas
index 4d73652..bc20f09 100644
--- a/packages/rtl/types.pas
+++ b/packages/rtl/types.pas
@@ -26,6 +26,7 @@ type
   TDoubleDynArray = array of Double;
   TJSValueDynArray = array of JSValue;
   TObjectDynArray = array of TObject;
+  TByteDynArray = array of Byte;
 
   TDuplicates = (dupIgnore, dupAccept, dupError);