diff --git a/Makefile b/Makefile
index 888c219..5ae8065 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,10 @@
 preserves.pdf: preserves.md preserves.css
 	google-chrome --headless --disable-gpu --print-to-pdf=$@ \
 		http://localhost:4000/preserves/preserves.html
+
+test-all:
+	make -C tests
+	(cd implementations/javascript; npm test)
+	(cd implementations/python; make test)
+	(cd implementations/racket/preserves; make testonly)
+	(cd implementations/rust; cargo test)