diff --git a/module_build_service/builder.py b/module_build_service/builder.py
index 3092526e..56e8b58d 100644
--- a/module_build_service/builder.py
+++ b/module_build_service/builder.py
@@ -384,6 +384,7 @@ It should NEVER be installed on any system as it will really mess up
 %install
 mkdir -p %buildroot/%_rpmconfigdir/macros.d 2>/dev/null |:
 echo %%dist %dist > %buildroot/%_rpmconfigdir/macros.d/macros.modules
+echo %%_module_build 1 >> %buildroot/%_rpmconfigdir/macros.d/macros.modules
 chmod 644 %buildroot/%_rpmconfigdir/macros.d/macros.modules