diff --git a/ports/zephyr/prj_base.conf b/ports/zephyr/prj_base.conf
index fbcedf2600..58c65f14de 100644
--- a/ports/zephyr/prj_base.conf
+++ b/ports/zephyr/prj_base.conf
@@ -1,4 +1,4 @@
-CONFIG_LEGACY_KERNEL=n
+CONFIG_BUILD_OUTPUT_BIN=y
 CONFIG_REBOOT=y
 
 CONFIG_STDOUT_CONSOLE=y