diff --git a/zephyr/Makefile b/zephyr/Makefile
index d0dce488db..501fb0a310 100644
--- a/zephyr/Makefile
+++ b/zephyr/Makefile
@@ -15,6 +15,8 @@ BOARD ?= qemu_x86
 # Zephyr 1.6.0
 OUTDIR_PREFIX = $(BOARD)
 
+FROZEN_DIR = scripts
+
 # Zephyr (generated) config files - must be defined before include below
 Z_SYSGEN_H = outdir/$(OUTDIR_PREFIX)/misc/generated/sysgen/sysgen.h
 Z_EXPORTS = outdir/$(OUTDIR_PREFIX)/Makefile.export
@@ -36,6 +38,7 @@ SRC_C = main.c \
 	lib/utils/printf.c \
 	lib/utils/pyexec.c \
 	lib/mp-readline/readline.c \
+	$(BUILD)/frozen.c \
 	$(SRC_MOD)
 
 OBJ = $(PY_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
diff --git a/zephyr/mpconfigport.h b/zephyr/mpconfigport.h
index f125ab3993..5d021b6aa2 100644
--- a/zephyr/mpconfigport.h
+++ b/zephyr/mpconfigport.h
@@ -32,6 +32,7 @@
 #define MICROPY_PY_BUILTINS_COMPLEX (0)
 #define MICROPY_HW_BOARD_NAME "zephyr-generic"
 #define MICROPY_HW_MCU_NAME "unknown-cpu"
+#define MICROPY_MODULE_FROZEN_STR   (1)
 
 typedef int mp_int_t; // must be pointer size
 typedef unsigned mp_uint_t; // must be pointer size