diff --git a/MANIFEST.in b/MANIFEST.in
index 9e5ecec..3d9dcbe 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,3 +1,3 @@
 include *.md
 recursive-include docs *.md *.py Makefile
-recursive-include tests *.py
+graft tests