diff --git a/Makefile b/Makefile
index ead7f97..022a60f 100644
--- a/Makefile
+++ b/Makefile
@@ -15,5 +15,5 @@ dev-requirements-py3:
 	pip freeze | grep -v -e reppy > dev-requirements-py3.txt
 
 clean:
-	rm -rf build dist *.egg-info
+	rm -rf build dist *.egg-info reppy/*.so
 	find . -name '*.pyc' | xargs --no-run-if-empty rm