diff --git a/tasks/main.yml b/tasks/main.yml
index 8e982b9..5a32d21 100644
--- a/tasks/main.yml
+++ b/tasks/main.yml
@@ -1,9 +1,22 @@
+- name: Include OS-specific variables.
+  include_vars: "{{ ansible_os_family }}.yml"
+
+- name: Add CentOS repository
+  block:
+  
+  - name: Add Docker repository.
+    get_url:
+      url: "https://download.docker.com/linux/centos/docker-ce.repo"
+      dest: '/etc/yum.repos.d/docker-ce.repo'
+      owner: root
+      group: root
+      mode: 0644
+  when: ansible_os_family == "RedHat"
+  become: true
+
 - name: Install Docker.
   package:
-    name:
-      - docker
-      - python-docker
-      - docker-compose
+    name: "{{  docker_package }}"
     state: present
   notify: restart docker
   become: true
diff --git a/tests/inventory b/tests/inventory
new file mode 100644
index 0000000..2fbb50c
--- /dev/null
+++ b/tests/inventory
@@ -0,0 +1 @@
+localhost
diff --git a/tests/test.yml b/tests/test.yml
new file mode 100644
index 0000000..748fdfa
--- /dev/null
+++ b/tests/test.yml
@@ -0,0 +1,4 @@
+---
+- hosts: all
+  roles:
+    - docker
diff --git a/vars/Archlinux.yml b/vars/Archlinux.yml
new file mode 100644
index 0000000..26ec4de
--- /dev/null
+++ b/vars/Archlinux.yml
@@ -0,0 +1,5 @@
+---
+docker_package:
+    - docker
+    - python-docker
+    - docker-compose
diff --git a/vars/RedHat.yml b/vars/RedHat.yml
new file mode 100644
index 0000000..acac966
--- /dev/null
+++ b/vars/RedHat.yml
@@ -0,0 +1,5 @@
+---
+docker_package:
+    - docker-ce
+    - python3-docker
+    - docker-compose-plugin