diff --git a/core/sys/Makefile.core-sys b/core/sys/Makefile.core-sys
new file mode 100644
index 000000000..7acc0115e
--- /dev/null
+++ b/core/sys/Makefile.core-sys
@@ -0,0 +1,3 @@
+core-sys_src = \
+arg.c	     compower.c  energest.c  mt.c	procinit.c  stimer.c \
+autostart.c  ctimer.c	 etimer.c    process.c	rtimer.c    timer.c