diff --git a/components/coap/component.mk b/components/coap/component.mk
index b5f6ec43c..86993b29e 100644
--- a/components/coap/component.mk
+++ b/components/coap/component.mk
@@ -7,3 +7,5 @@ COMPONENT_ADD_INCLUDEDIRS := port/include port/include/coap libcoap/include libc
 COMPONENT_OBJS = libcoap/src/address.o libcoap/src/async.o libcoap/src/block.o libcoap/src/coap_time.o libcoap/src/debug.o libcoap/src/encode.o libcoap/src/hashkey.o libcoap/src/mem.o libcoap/src/net.o libcoap/src/option.o libcoap/src/pdu.o libcoap/src/resource.o libcoap/src/str.o libcoap/src/subscribe.o libcoap/src/uri.o port/coap_io_socket.o
 
 COMPONENT_SRCDIRS := libcoap/src libcoap port
+
+COMPONENT_SUBMODULES += libcoap