diff --git a/Makefile b/Makefile
index 993b02c72..a8c915186 100644
--- a/Makefile
+++ b/Makefile
@@ -3,4 +3,9 @@ all:
 clean:	FORCE
 	rm -rf zerotier-core-crypto/target zerotier-network-hypervisor/target zerotier-system-service/target syncwhole/target aes-gmac-siv/target iblt/target
 
+test:
+	for i in */Cargo.toml; do cd $$(dirname $$i); cargo test || exit 1; cd ..; done
+
 FORCE:
+
+.PHONY: test