diff --git a/Makefile b/Makefile
index 4227873..2f2ea0d 100644
--- a/Makefile
+++ b/Makefile
@@ -54,8 +54,9 @@ style:
 	flake8
 	! grep -ri syncroniz */*
 	sphinx-build -W -b html ./docs/ ./docs/_build/html/
-	$(MAKE) travis-conf
-	git diff --exit-code
+	python3 scripts/make_travisconf.py | \
+		diff -q .travis.yml - > /dev/null || \
+		(echo 'travis.yml is outdated. Run `make travis-conf`.' && false)
 
 travis-conf:
 	python3 scripts/make_travisconf.py > .travis.yml