diff --git a/hack/__init__.py b/hack/__init__.py
index d390cde65cc04..e00530717a732 100644
--- a/hack/__init__.py
+++ b/hack/__init__.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2020 The Kubernetes Authors.
 #
diff --git a/hack/boilerplate/boilerplate.py b/hack/boilerplate/boilerplate.py
index 946fa05687550..a1dd7ec6b0811 100755
--- a/hack/boilerplate/boilerplate.py
+++ b/hack/boilerplate/boilerplate.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2015 The Kubernetes Authors.
 #
diff --git a/hack/boilerplate/boilerplate.py.txt b/hack/boilerplate/boilerplate.py.txt
index a2e72e5988e73..9fdb989ce7c5b 100644
--- a/hack/boilerplate/boilerplate.py.txt
+++ b/hack/boilerplate/boilerplate.py.txt
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright YEAR The Kubernetes Authors.
 #
diff --git a/hack/mkdocs_macros/__init__.py b/hack/mkdocs_macros/__init__.py
index 6bf03edf49b9e..07cf403f59564 100644
--- a/hack/mkdocs_macros/__init__.py
+++ b/hack/mkdocs_macros/__init__.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2020 The Kubernetes Authors.
 #
diff --git a/hack/mkdocs_macros/feature_stability_table.py b/hack/mkdocs_macros/feature_stability_table.py
index 3eb5750eb869a..577ed148a2786 100644
--- a/hack/mkdocs_macros/feature_stability_table.py
+++ b/hack/mkdocs_macros/feature_stability_table.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2020 The Kubernetes Authors.
 #
diff --git a/hack/verify-boilerplate.sh b/hack/verify-boilerplate.sh
index 3a5c6bf5b18af..ff7ee85dc8dfa 100755
--- a/hack/verify-boilerplate.sh
+++ b/hack/verify-boilerplate.sh
@@ -14,6 +14,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+set -o errexit
+set -o nounset
+set -o pipefail
+
 . "$(dirname "${BASH_SOURCE[0]}")/common.sh"
 
 files_need_boilerplate=()