diff --git a/Tools/ardupilotwaf/boards.py b/Tools/ardupilotwaf/boards.py
index afaf4ff808..8a3e4fadcb 100644
--- a/Tools/ardupilotwaf/boards.py
+++ b/Tools/ardupilotwaf/boards.py
@@ -96,6 +96,7 @@ class Board:
         if cfg.options.enable_scripting:
             env.DEFINES.update(
                 ENABLE_SCRIPTING = 1,
+                ENABLE_HEAP = 1,
                 LUA_32BITS = 1,
                 )