diff --git a/run_tests.sh b/run_tests.sh
index 26e6463..591825c 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -1,2 +1,2 @@
 #!/bin/bash
-nosetests tests --exclude-dir=stacktach --with-coverage --cover-package=stacktach,worker,verifier
+nosetests tests --exclude-dir=stacktach --with-coverage --cover-package=stacktach,worker,verifier --cover-erase