diff --git a/sys/include/net/gcoap.h b/sys/include/net/gcoap.h
index 87bc62772056f1782b57a7aa222a8025e50fb63b..ebac4e16d4264c071ed4d9b5cfee70f60ba3301c 100644
--- a/sys/include/net/gcoap.h
+++ b/sys/include/net/gcoap.h
@@ -386,6 +386,13 @@ extern "C" {
 #define GCOAP_OBS_INIT_UNUSED   (-2)
 /** @} */
 
+/**
+ * @brief Stack size for module thread
+ */
+#ifndef GCOAP_STACK_SIZE
+#define GCOAP_STACK_SIZE (THREAD_STACKSIZE_DEFAULT + DEBUG_EXTRA_STACKSIZE)
+#endif
+
 /**
  * @brief   A modular collection of resources for a server
  */
diff --git a/sys/net/application_layer/coap/gcoap.c b/sys/net/application_layer/coap/gcoap.c
index 55fc98ae069fabb50aa7c75493bf33098a006964..cd933dbe2cfad939fe12b7b4b9ade34f0954b96a 100644
--- a/sys/net/application_layer/coap/gcoap.c
+++ b/sys/net/application_layer/coap/gcoap.c
@@ -26,9 +26,6 @@
 #define ENABLE_DEBUG (0)
 #include "debug.h"
 
-/** @brief Stack size for module thread */
-#define GCOAP_STACK_SIZE (THREAD_STACKSIZE_DEFAULT + DEBUG_EXTRA_STACKSIZE)
-
 /* Internal functions */
 static void *_event_loop(void *arg);
 static void _listen(sock_udp_t *sock);