diff --git a/Makefile b/Makefile
index 0336123..1ce2450 100644
--- a/Makefile
+++ b/Makefile
@@ -1,15 +1,29 @@
-.PHONY.: test
-test:
-	nimble test
+# Make does not offer a recursive wildcard function, so here's one:
+ rwildcard=$(wildcard $1$2) $(foreach d,$(wildcard $1*),$(call rwildcard,$d/,$2))
 
-.PHONY.: build
+SOURCES=$(call rwildcard,src/,*.nim)
+TEST_SOURCES=$(wildcard tests/*.nim)
+TESTS=$(patsubst %.nim,bin/%,$(TEST_SOURCES))
+
+.PHONY: test
+test: $(TESTS) $(SOURCES)
+	@for t in $(TESTS); do $$t; done
+
+.PHONY: watch-tests
+watch-tests:
+	watch 'make test' src tests --wait=10
+
+.PHONY: build
 build: test
 	nimble build
 
-.PHONY.: install
+.PHONY: install
 install: test
 	nimble install
 
 diagrams: doc/vcard3.mmd doc/vcard4.mmd
 	mmdc -i doc/vcard3.mmd -o doc/vcard3.png
 	mmdc -i doc/vcard4.mmd -o doc/vcard4.png
+
+bin/tests/%: tests/%.nim $(SOURCES)
+	nim --outdir:bin/tests c $(patsubst bin/%,%.nim,$@)