diff --git a/net/Makefile b/net/Makefile
index c4b86f4de99..7a9cf03d5b8 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -61,6 +61,7 @@ include iob/Make.defs
 include arp/Make.defs
 include icmp/Make.defs
 include icmpv6/Make.defs
+include neighbor/Make.defs
 include igmp/Make.defs
 include tcp/Make.defs
 include udp/Make.defs