diff --git a/tools/pretty_tox.sh b/tools/pretty_tox.sh
index a5a6076..07c35a0 100755
--- a/tools/pretty_tox.sh
+++ b/tools/pretty_tox.sh
@@ -1,4 +1,6 @@
-#!/bin/sh
+#!/usr/bin/env bash
+
+set -o pipefail
 
 TESTRARGS=$1
 python setup.py testr --slowest --testr-args="--subunit $TESTRARGS" | subunit2pyunit