diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index c6c053b7e..92274bb93 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,5 +1,25 @@
 ---
 repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v1.4.0
+    hooks:
+      - id: trailing-whitespace
+      - id: mixed-line-ending
+      - id: check-byte-order-marker
+      - id: check-executables-have-shebangs
+      - id: check-merge-conflict
+      - id: debug-statements
+      - id: check-yaml
+        files: .*\.(yaml|yml)$
+  - repo: https://github.com/adrienverge/yamllint.git
+    rev: v1.12.1
+    hooks:
+      - id: yamllint
+        files: \.(yaml|yml)$
+        types: [file, yaml]
+        # uncommend once a new yamllint release is made:
+        # entry: yamllint --strict
+
   - repo: https://github.com/openstack-dev/bashate.git
     rev: 0.6.0
     hooks:
diff --git a/.yamllint b/.yamllint
new file mode 100644
index 000000000..69b4b4159
--- /dev/null
+++ b/.yamllint
@@ -0,0 +1,6 @@
+---
+extends: default
+
+rules:
+  line-length:
+    max: 180
diff --git a/config/environments/rdocloud.yml b/config/environments/rdocloud.yml
index bdd02e1ef..971b90635 100644
--- a/config/environments/rdocloud.yml
+++ b/config/environments/rdocloud.yml
@@ -1,3 +1,4 @@
+---
 os_username: "{{ lookup('env','OS_USERNAME') }}"
 os_password: "{{ lookup('env','OS_PASSWORD') }}"
 os_tenant_name: "{{ lookup('env','OS_TENANT_NAME') }}"
@@ -39,9 +40,8 @@ mtu_interface:
 undercloud_local_mtu: "{{ mtu }}"
 overcloud_neutron_global_physnet_mtu: "{{ mtu }}"
 
-run_tripleo_validations: True
+run_tripleo_validations: true
 
 # Browbeat settings
-cloud_name: rdocloud
 elastic_host: browbeat.test.com
 grafana_host: browbeat.test.com
diff --git a/roles/overcloud-deploy/files/hardware_environments/virt/network_configs/single_nic_vlans_ipv4/single_nic_vlans_ipv4.yml b/roles/overcloud-deploy/files/hardware_environments/virt/network_configs/single_nic_vlans_ipv4/single_nic_vlans_ipv4.yml
index 42f019bd2..6ecebe949 100644
--- a/roles/overcloud-deploy/files/hardware_environments/virt/network_configs/single_nic_vlans_ipv4/single_nic_vlans_ipv4.yml
+++ b/roles/overcloud-deploy/files/hardware_environments/virt/network_configs/single_nic_vlans_ipv4/single_nic_vlans_ipv4.yml
@@ -1,3 +1,4 @@
+---
 # note the EC2MetadataIp: value should match the value in
 # /home/stack/undercloud.conf for key local_ip
 # # EC2MetadataIp: "local_ip"
@@ -19,4 +20,4 @@ parameter_defaults:
   ControlPlaneSubnetCidr: "24"
   ControlPlaneDefaultRoute: 192.0.2.1
   EC2MetadataIp: 192.0.2.1
-  DnsServers: ["192.168.23.1", "8.8.8.8",]
+  DnsServers: ["192.168.23.1", "8.8.8.8"]
diff --git a/roles/validate-tempest/defaults/main.yml b/roles/validate-tempest/defaults/main.yml
index 1d3be9675..5470aadd7 100644
--- a/roles/validate-tempest/defaults/main.yml
+++ b/roles/validate-tempest/defaults/main.yml
@@ -4,7 +4,6 @@ floating_ip_cidr: "{{ undercloud_network_cidr }}"
 public_net_pool_start: "{{ floating_ip_cidr|nthhost(100) }}"
 public_net_pool_end: "{{ floating_ip_cidr|nthhost(120) }}"
 public_net_gateway: "{{ floating_ip_cidr|nthhost(1) }}"
-tempest_log_file: 'tempest_output.log'
 test_white_regex: "{{ test_regex|default('smoke') }}"
 test_black_regex: []
 check_tempest_bugs: false
@@ -22,7 +21,7 @@ tempest_config: true
 tempest_overcloud: true
 run_tempest: false
 post_tempest: true
-tempest_format: packages # venv or packages or container
+tempest_format: packages  # venv or packages or container
 tempest_container_registry: >-
   {% if (undercloud_enable_tempest is defined) and undercloud_enable_tempest|bool -%}
   {{ local_docker_registry_host }}:8787/{{ docker_registry_namespace }}
@@ -60,14 +59,20 @@ tempest_plugins: >-
   [ "python-keystone-tests", "python-neutron-tests" ]
   {%- endif -%}
 
-tempest_extra_config: {}# A dict containing values which needs to be overridden in tempest.conf
+tempest_extra_config: {}  # A dict containing values which needs to be overridden in tempest.conf
 skip_file_src: "skip_file.j2"
 skip_file: skip_file
 tempest_until_failure: false
 tempest_exit_on_failure: true
 # Set tempest_version for different release
 # For forked-tempest, we have branched name in synced with releases.
-tempest_version_dict: { 'newton': 'newton', 'ocata': '16.1.0', 'pike': '17.1.0', 'queens': '17.2.0', 'rocky': '19.0.0', 'master': 'master'}
+tempest_version_dict:
+  newton: 'newton'
+  ocata: '16.1.0'
+  pike: '17.1.0'
+  queens: '17.2.0'
+  rocky: '19.0.0'
+  master: 'master'
 tempest_version: "{{ tempest_version_dict[release] }}"
 tempest_conf_version_dict: {'ocata': '1.1.3', 'pike': '1.1.3', 'queens': '1.1.4', 'rocky': 'master', 'master': 'master'}
 tempest_conf_version: "{{ tempest_conf_version_dict[release] }}"
diff --git a/roles/validate-ui/.travis.yml b/roles/validate-ui/.travis.yml
index 36bbf6208..121cc4993 100644
--- a/roles/validate-ui/.travis.yml
+++ b/roles/validate-ui/.travis.yml
@@ -9,7 +9,7 @@ sudo: false
 addons:
   apt:
     packages:
-    - python-pip
+      - python-pip
 
 install:
   # Install ansible
@@ -26,4 +26,4 @@ script:
   - ansible-playbook tests/test.yml -i tests/inventory --syntax-check
 
 notifications:
-  webhooks: https://galaxy.ansible.com/api/v1/notifications/
\ No newline at end of file
+  webhooks: https://galaxy.ansible.com/api/v1/notifications/
diff --git a/tox.ini b/tox.ini
index 747da8e09..728707aaa 100644
--- a/tox.ini
+++ b/tox.ini
@@ -50,7 +50,10 @@ commands = bash -c ci-scripts/releasenotes_tox.sh
 
 [testenv:linters]
 commands =
-    {[testenv:bashate]commands}
+    # check only modified files:
+    python -m pre_commit run --source HEAD^ --origin HEAD
+    # in the future we may want to check entire repository:
+    # python -m pre_commit run yamllint --all-files
     {[testenv:pep8]commands}
     {[testenv:ansible-lint]commands}
     {[testenv:validate-jinja]commands}