diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
index af7a1e0..96b4938 100644
--- a/.github/FUNDING.yml
+++ b/.github/FUNDING.yml
@@ -1,4 +1,4 @@
 # These are supported funding model platforms
-
+---
 github: geerlingguy
 patreon: geerlingguy
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..a86f458
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,77 @@
+---
+name: CI
+'on':
+  pull_request:
+  push:
+    branches:
+      - master
+  schedule:
+    - cron: "0 5 * * 4"
+
+jobs:
+
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out the codebase.
+        uses: actions/checkout@v2
+
+      - name: Set up Python 3.
+        uses: actions/setup-python@v2
+        with:
+          python-version: '3.x'
+
+      - name: Install test dependencies.
+        run: pip3 install yamllint ansible-lint
+
+      - name: Lint code.
+        run: |
+          yamllint .
+          ansible-lint
+
+  integration:
+    name: Integration
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os:
+          - macos-10.15
+
+    steps:
+      - name: Check out the codebase.
+        uses: actions/checkout@v2
+
+      - name: Uninstall GitHub Actions' built-in Homebrew.
+        run: tests/uninstall-homebrew.sh
+
+      - name: Uninstall GitHub Actions' built-in browser installs.
+        run: |
+          sudo rm -rf /Applications/Firefox.app
+          sudo rm -rf /Applications/Google\ Chrome.app
+
+      - name: Install test dependencies.
+        run: sudo pip3 install ansible
+
+      - name: Set up the test environment.
+        run: |
+          cp tests/ansible.cfg ./ansible.cfg
+          cp tests/inventory ./inventory
+          cp tests/config.yml ./config.yml
+          ansible-galaxy install -r requirements.yml -p ./roles
+
+      - name: Test the playbook's syntax.
+        run: ansible-playbook tests/test.yml --syntax-check
+
+      - name: Test the playbook.
+        run: ansible-playbook tests/test.yml
+        env:
+          ANSIBLE_FORCE_COLOR: '1'
+
+      - name: Idempotence check.
+        run: |
+          idempotence=$(mktemp)
+          ansible-playbook tests/test.yml | tee -a ${idempotence}
+          tail ${idempotence} | grep -q 'changed=0.*failed=0' && (echo 'Idempotence test: pass' && exit 0) || (echo 'Idempotence test: fail' && exit 1)
+        env:
+          ANSIBLE_FORCE_COLOR: '1'
diff --git a/.yamllint b/.yamllint
new file mode 100644
index 0000000..84ecaec
--- /dev/null
+++ b/.yamllint
@@ -0,0 +1,10 @@
+---
+extends: default
+
+rules:
+  line-length:
+    max: 180
+    level: warning
+
+ignore: |
+  .github/stale.yml
diff --git a/README.md b/README.md
index 28499a6..b7d6eea 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 # Mac Development Ansible Playbook
 
-[![Build Status](https://travis-ci.org/geerlingguy/mac-dev-playbook.svg?branch=master)](https://travis-ci.org/geerlingguy/mac-dev-playbook)
+[![CI][badge-gh-actions]][link-gh-actions]
 
 This playbook installs and configures most of the software I use on my Mac for web and software development. Some things in macOS are slightly difficult to automate, so I still have some manual installation steps, but at least it's all documented here.
 
@@ -177,3 +177,6 @@ Check out [Ansible for DevOps](https://www.ansiblefordevops.com/), which teaches
 ## Author
 
 [Jeff Geerling](https://www.jeffgeerling.com/), 2014 (originally inspired by [MWGriffin/ansible-playbooks](https://github.com/MWGriffin/ansible-playbooks)).
+
+[badge-gh-actions]: https://github.com/geerlingguy/mac-dev-playbook/workflows/CI/badge.svg?event=push
+[link-gh-actions]: https://github.com/geerlingguy/mac-dev-playbook/actions?query=workflow%3ACI
diff --git a/default.config.yml b/default.config.yml
index f4768e4..38ff438 100644
--- a/default.config.yml
+++ b/default.config.yml
@@ -1,11 +1,11 @@
 ---
 downloads: ~/.ansible-downloads/
 
-configure_dotfiles: yes
-configure_terminal: yes
-configure_osx: yes
+configure_dotfiles: true
+configure_terminal: true
+configure_osx: true
 
-configure_sudoers: no
+configure_sudoers: false
 sudoers_custom_config: ''
 # Example:
 # sudoers_custom_config: |
@@ -13,7 +13,7 @@ sudoers_custom_config: ''
 #   %admin ALL=(ALL) NOPASSWD: ALL
 
 dotfiles_repo: https://github.com/geerlingguy/dotfiles.git
-dotfiles_repo_accept_hostkey: yes
+dotfiles_repo_accept_hostkey: true
 dotfiles_repo_local_destination: ~/Development/GitHub/dotfiles
 dotfiles_files:
   - .zshrc
@@ -80,21 +80,21 @@ osx_script: "~/.osx --no-restart"
 # Note: You are responsible for making sure the required package managers are
 # installed, eg. through homebrew.
 composer_packages: []
-  # - name: drush
-  #   state: present # present/absent, default: present
-  #   version: "^8.1" # default: N/A
+# - name: drush
+#   state: present # present/absent, default: present
+#   version: "^8.1" # default: N/A
 gem_packages: []
-  # - name: bundler
-  #   state: present # present/absent/latest, default: present
-  #   version: "~> 1.15.1" # default: N/A
+# - name: bundler
+#   state: present # present/absent/latest, default: present
+#   version: "~> 1.15.1" # default: N/A
 npm_packages: []
-  # - name: webpack
-  #   state: present # present/absent/latest, default: present
-  #   version: "^2.6" # default: N/A
+# - name: webpack
+#   state: present # present/absent/latest, default: present
+#   version: "^2.6" # default: N/A
 pip_packages: []
-  # - name: mkdocs
-  #   state: present # present/absent/latest, default: present
-  #   version: "0.16.3" # default: N/A
+# - name: mkdocs
+#   state: present # present/absent/latest, default: present
+#   version: "0.16.3" # default: N/A
 
 # Glob pattern to ansible task files to run after all other tasks are finished.
 post_provision_tasks: []
diff --git a/tasks/ansible-setup.yml b/tasks/ansible-setup.yml
index efa9508..d474b4a 100644
--- a/tasks/ansible-setup.yml
+++ b/tasks/ansible-setup.yml
@@ -8,7 +8,7 @@
   file:
     path: /etc/ansible
     state: directory
-  become: yes
+  become: true
 
 - name: Symlink /usr/local/etc/ansible to /etc/ansible.
   file:
diff --git a/tasks/extra-packages.yml b/tasks/extra-packages.yml
index ee9254c..643cd41 100644
--- a/tasks/extra-packages.yml
+++ b/tasks/extra-packages.yml
@@ -12,7 +12,7 @@
     name: "{{ item.name | default(item) }}"
     state: "{{ item.state | default('present') }}"
     version: "{{ item.version | default(omit) }}"
-    global: yes
+    global: true
     executable: "{{ item.executable | default(omit) }}"
   with_items: "{{ npm_packages }}"
 
@@ -29,6 +29,6 @@
     name: "{{ item.name | default(item) }}"
     state: "{{ item.state | default('present') }}"
     version: "{{ item.version | default(omit) }}"
-    user_install: no
+    user_install: false
     executable: "{{ item.executable | default(omit) }}"
   with_items: "{{ gem_packages }}"
diff --git a/tasks/sudoers.yml b/tasks/sudoers.yml
index 34894af..55cf05c 100644
--- a/tasks/sudoers.yml
+++ b/tasks/sudoers.yml
@@ -18,4 +18,4 @@
     dest: /private/etc/sudoers.d/custom
     mode: 0440
     validate: 'visudo -cf %s'
-  become: yes
+  become: true
diff --git a/tasks/terminal.yml b/tasks/terminal.yml
index 278450d..618faf6 100644
--- a/tasks/terminal.yml
+++ b/tasks/terminal.yml
@@ -4,7 +4,7 @@
   shell: defaults read com.apple.terminal 'Default Window Settings'
   register: terminal_theme
   changed_when: false
-  check_mode: no
+  check_mode: false
 
 - name: Ensure custom Terminal profile is added.
   shell: open files/terminal/JJG-Term.terminal
diff --git a/tests/ansible.cfg b/tests/ansible.cfg
new file mode 100644
index 0000000..6c19e9a
--- /dev/null
+++ b/tests/ansible.cfg
@@ -0,0 +1,3 @@
+[defaults]
+inventory = inventory
+roles_path = ../:../roles:./roles
diff --git a/tests/config.yml b/tests/config.yml
index fefa4b3..e95fb92 100644
--- a/tests/config.yml
+++ b/tests/config.yml
@@ -1,3 +1,4 @@
+---
 homebrew_installed_packages:
   - autoconf
   - bash-completion
diff --git a/tests/inventory b/tests/inventory
new file mode 100644
index 0000000..13cfabe
--- /dev/null
+++ b/tests/inventory
@@ -0,0 +1,2 @@
+[local]
+localhost ansible_connection=local
diff --git a/tests/uninstall-homebrew.sh b/tests/uninstall-homebrew.sh
new file mode 100755
index 0000000..d6d4c96
--- /dev/null
+++ b/tests/uninstall-homebrew.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+#
+# Uninstalls Homebrew using the official uninstall script.
+
+# Download and run the uninstall script.
+curl -sLO https://raw.githubusercontent.com/Homebrew/install/master/uninstall.sh
+chmod +x ./uninstall.sh
+sudo ./uninstall.sh --force
+
+# Clean up Homebrew directories.
+sudo rm -rf /usr/local/Homebrew
+sudo rm -rf /usr/local/Caskroom
+sudo rm -rf /usr/local/bin/brew