diff --git a/examples/playbook.yml b/examples/playbook.yml
index 501599d..7f45aad 100644
--- a/examples/playbook.yml
+++ b/examples/playbook.yml
@@ -1,3 +1,4 @@
+---
 - name: Set up repo builds
   hosts: repo_all
   user: root
diff --git a/tests/ansible-role-requirements.yml b/tests/ansible-role-requirements.yml
index 719bc28..ea93d0d 100644
--- a/tests/ansible-role-requirements.yml
+++ b/tests/ansible-role-requirements.yml
@@ -1,3 +1,4 @@
+---
 - name: apt_package_pinning
   src: https://git.openstack.org/openstack/openstack-ansible-apt_package_pinning
   scm: git
diff --git a/tests/test-data.yml b/tests/test-data.yml
index beeeba0..bbfac85 100644
--- a/tests/test-data.yml
+++ b/tests/test-data.yml
@@ -1,3 +1,4 @@
+---
 # Test data output from the py_pkgs lookup
 # To produce a fresh version of this, execute:
 # /opt/ansible-runtime/bin/python /etc/ansible/roles/plugins/lookup/py_pkgs.py \
diff --git a/zuul.d/project.yaml b/zuul.d/project.yaml
index 4e2c3ee..6fa95ea 100644
--- a/zuul.d/project.yaml
+++ b/zuul.d/project.yaml
@@ -1,3 +1,4 @@
+---
 # Copyright 2017, Rackspace US, Inc.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");