+ gcc -I $${C_INCLUDE_PATH:-.} $< -g -o $@ -lrmr_nng -lnng -lpthread -lm
+
+
+
+# ----- si test builds -------------------------------------------------------------
+
+sender_si: sender.c
+ gcc -I $${C_INCLUDE_PATH:-.} $< -g -o $@ -lrmr_si -lpthread -lm
+
+receiver_si: receiver.c
+ gcc -I $${C_INCLUDE_PATH:-.} $< -g -o $@ -lrmr_si -lpthread -lm
+
+
+# --------- housekeeping -----------------------------------------------------------