diff --git a/python-cytoolz.spec b/python-cytoolz.spec
index fbe7d4a..504be58 100644
--- a/python-cytoolz.spec
+++ b/python-cytoolz.spec
@@ -53,6 +53,7 @@ export CFLAGS="%{optflags}"
 %check
 mkdir testing
 pushd testing
+export PYTHONDONTWRITEBYTECODE=1
 %pytest_arch ../cytoolz/tests
 popd