diff --git a/Makefile.include b/Makefile.include
index 1d4896043..6a03d9c34 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -28,7 +28,7 @@ endif
 
 SYSTEM  = process.c procinit.c service.c autostart.c
 THREADS = mt.c
-LIBS    = memb.c timer.c list.c etimer.c
+LIBS    = memb.c timer.c list.c etimer.c crtk.c
 CFS     = cfs.c cfs-ram.c
 CTK     = ctk.c
 UIP     = uip.c uiplib.c resolv.c tcpip.c psock.c hc.c uip-split.c \