diff --git a/README.md b/README.md
index a5b04a9..19a8767 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
 # Ansible Collection
 
-Opinionated set of roles to configure reasonable defaults for newly provisioned Debian / Ubuntu VMs running Docker. The repository provides a ready-to-use Ansible Collection (`studio.ansible`) containing reusable roles.
+Opinionated set of roles to configure reasonable defaults for newly provisioned virtual machines. The repository provides a ready-to-use Ansible Collection (`studio.ansible`) containing reusable roles.
+
+Currently only supports Debian-based systems.
diff --git a/galaxy.yml b/galaxy.yml
index 9e0f03e..c79a793 100644
--- a/galaxy.yml
+++ b/galaxy.yml
@@ -3,8 +3,9 @@
 namespace: studio
 name: ansible
 readme: README.md
-version: 1.0.0
+version: 0.0.1
 authors:
   - Studio Vitali
 description: Studio Ansible collection containing common roles
-license: MIT
+license:
+  - MIT
diff --git a/meta/runtime.yml b/meta/runtime.yml
new file mode 100644
index 0000000..1e85b01
--- /dev/null
+++ b/meta/runtime.yml
@@ -0,0 +1,2 @@
+---
+requires_ansible: ">=2.15.0"
diff --git a/roles/base/tasks/main.yml b/roles/base/tasks/main.yml
index c398fff..9535d89 100644
--- a/roles/base/tasks/main.yml
+++ b/roles/base/tasks/main.yml
@@ -10,7 +10,6 @@
     update_cache: true
     upgrade: dist
     cache_valid_time: 3600
-  when: ansible_facts['os_family'] == "Debian" ## only on Debian / Ubuntu systems
   become: true
 
 - name: Install essential system utilities
@@ -26,7 +25,6 @@
       - unattended-upgrades
     state: present
     update_cache: true
-  when: ansible_facts['os_family'] == "Debian"
   become: true
 #
 # - name: Enable unattended-upgrades
@@ -37,5 +35,3 @@
 #       APT::Periodic::Unattended-Upgrade "1";
 #     mode: "0644"
 #   when: ansible_facts['os_family'] == "Debian"
-
-## SCHEDULE REBOOTS 4 kernel upgrades: with cron, unattended-upgrades or action workflows?
diff --git a/roles/docker/tasks/main.yml b/roles/docker/tasks/main.yml
index 4229019..a1f1d05 100644
--- a/roles/docker/tasks/main.yml
+++ b/roles/docker/tasks/main.yml
@@ -1,35 +1,76 @@
 ---
-- name: Install necessary Docker packages
-  ansible.builtin.apt:
-    name:
-      - docker.io
-      - docker-compose
-    state: present
-  when: ansible_facts['os_family'] == "Debian" ## Debian / Ubuntu
+- name: Install Docker
   become: true
+  block:
+    - name: Install Docker prerequisites
+      ansible.builtin.apt:
+        name:
+          - ca-certificates
+          - curl
+          - python3-debian ## needed for the deb822 module
+        state: present
+        update_cache: true
 
-- name: Ensure Docker service is running
-  ansible.builtin.service:
-    name: docker
-    state: started
-    enabled: true
+    - name: Add Docker official APT repository (DEB822 format)
+      ansible.builtin.deb822_repository:
+        name: docker
+        types: deb
+        uris: "https://download.docker.com/linux/{{ ansible_facts['distribution'] | lower }}"
+        suites: "{{ ansible_facts['distribution_release'] }}"
+        components: stable
+        signed_by: "https://download.docker.com/linux/{{ ansible_facts['distribution'] | lower }}/gpg"
+        state: present
 
-- name: Create docker user for container execution
-  ansible.builtin.user:
-    name: docker
-    state: present
-    system: true
-    shell: /usr/sbin/nologin
-    groups: docker
-    append: true
-    create_home: false
+    - name: Install Docker CE packages
+      ansible.builtin.apt:
+        name:
+          - docker-ce
+          - docker-ce-cli
+          - containerd.io
+          - docker-buildx-plugin
+          - docker-compose-plugin
+        state: present
+        update_cache: true
+
+    - name: Ensure Docker service is running and enabled
+      ansible.builtin.service:
+        name: docker
+        state: started
+        enabled: true
+
+- name: Configure deployment user for Docker
+  when: deployment_public_ssh_key is defined
   become: true
+  block:
+    - name: Add deployment user to docker group
+      ansible.builtin.user:
+        name: deployment
+        groups: docker
+        append: true
 
-- name: Create target for docker compose
-  ansible.builtin.file:
-    path: /opt/docker
-    state: directory
-    owner: deployment
-    group: deployment
-    mode: "0755"
+    - name: Create target for docker compose
+      ansible.builtin.file:
+        path: /opt/docker
+        state: directory
+        owner: deployment
+        group: deployment
+        mode: "0755"
+
+- name: Create app user for secure container execution
   become: true
+  block:
+    - name: Create appuser group
+      ansible.builtin.group:
+        name: appuser
+        state: present
+        gid: 9999
+
+    - name: Create appuser
+      ansible.builtin.user:
+        name: appuser
+        state: present
+        uid: 9999
+        group: appuser
+        system: true
+        shell: /usr/sbin/nologin
+        create_home: false
diff --git a/roles/security/handlers/main.yml b/roles/security/handlers/main.yml
index 6998953..cad74d8 100644
--- a/roles/security/handlers/main.yml
+++ b/roles/security/handlers/main.yml
@@ -1,5 +1,5 @@
 ---
 - name: Restart sshd
   ansible.builtin.service:
-    name: sshd
+    name: ssh
     state: restarted
diff --git a/roles/security/tasks/main.yml b/roles/security/tasks/main.yml
index a0b5b33..5d4c252 100644
--- a/roles/security/tasks/main.yml
+++ b/roles/security/tasks/main.yml
@@ -1,35 +1,35 @@
 ---
-- name: Create SSH drop-in directory
-  ansible.builtin.file:
-    path: /etc/ssh/sshd_config.d
-    state: directory
-    owner: root
-    group: root
-    mode: "0755"
+- name: Harden SSH configuration
   become: true
+  block:
+    - name: Create SSH drop-in directory
+      ansible.builtin.file:
+        path: /etc/ssh/sshd_config.d
+        state: directory
+        owner: root
+        group: root
+        mode: "0755"
 
-- name: Harden SSH configuration with drop-in template
-  ansible.builtin.template:
-    src: sshd.conf.j2
-    dest: /etc/ssh/sshd_config.d/sshd.conf
-    owner: root
-    group: root
-    mode: "0644"
-    validate: "sshd -t -f %s"
-  notify: Restart sshd
+    - name: Harden SSH configuration with drop-in template
+      ansible.builtin.template:
+        src: sshd.conf.j2
+        dest: /etc/ssh/sshd_config.d/sshd.conf
+        owner: root
+        group: root
+        mode: "0644"
+      notify: Restart sshd
+
+- name: Enable fail2ban
   become: true
+  block:
+    - name: Install fail2ban
+      ansible.builtin.apt:
+        name:
+          - fail2ban
+        state: present
 
-- name: Install fail2ban
-  ansible.builtin.apt:
-    name:
-      - fail2ban
-    state: present
-  when: ansible_facts['os_family'] == "Debian"
-  become: true
-
-- name: Start fail2ban
-  ansible.builtin.service:
-    name: fail2ban
-    state: started
-    enabled: yes
-  when: ansible_facts['os_family'] == "Debian"
+    - name: Start fail2ban
+      ansible.builtin.service:
+        name: fail2ban
+        state: started
+        enabled: yes
diff --git a/roles/users/tasks/main.yml b/roles/users/tasks/main.yml
index 6628891..e416529 100644
--- a/roles/users/tasks/main.yml
+++ b/roles/users/tasks/main.yml
@@ -1,38 +1,42 @@
 ---
-# - name: Create primary admin user
-#   ansible.builtin.user:
-#     name: sysadmin
-#     groups: sudo
-#     append: yes
-#     shell: /bin/bash
-#     create_home: yes
-#   become: true
-
-# - name: Add SSH public key for sysadmin
-#   ansible.posix.authorized_key:
-#     user: sysadmin
-#     state: present
-#     key: "{{ sysadmin_public_ssh_key }}"
-#   become: true
-
-# - name: Allow passwordless sudo to sysadmin user
-#   ansible.builtin.copy:
-#     dest: /etc/sudoers.d/sysadmin
-#     content: "sysadmin ALL=(ALL) NOPASSWD: ALL"
-#     mode: "0440"
-#     validate: /usr/sbin/visudo -cf %s
-#   become: true
-
-- name: Create deployment user for CI/CD
-  ansible.builtin.user:
-    name: deployment
-    shell: /bin/bash
-    create_home: yes
+- name: Set up primary sysadmin user
+  when: sysadmin_public_ssh_key is defined
   become: true
+  block:
+    - name: Create sysadmin user
+      ansible.builtin.user:
+        name: "{{ sysadmin_user }}"
+        groups: sudo
+        append: yes
+        shell: /bin/bash
+        create_home: yes
 
-- name: Add SSH public key for deployment user
-  ansible.posix.authorized_key:
-    user: deployment
-    state: present
-    key: "{{ deployment_public_ssh_key }}"
+    - name: Add SSH public key
+      ansible.posix.authorized_key:
+        user: "{{ sysadmin_user }}"
+        state: present
+        key: "{{ sysadmin_public_ssh_key }}"
+
+    - name: Allow passwordless sudo
+      ansible.builtin.copy:
+        dest: /etc/sudoers.d/sudo-nopasswd
+        content: "%sudo ALL=(ALL) NOPASSWD: ALL"
+        mode: "0440"
+        validate: /usr/sbin/visudo -cf %s
+
+
+- name: Set up deployment user for CI/CD
+  when: deployment_public_ssh_key is defined
   become: true
+  block:
+    - name: Create deployment user
+      ansible.builtin.user:
+        name: deployment
+        shell: /bin/bash
+        create_home: yes
+
+    - name: Add SSH public key
+      ansible.posix.authorized_key:
+        user: deployment
+        state: present
+        key: "{{ deployment_public_ssh_key }}"