---
- name: Install borg
  apt:
    name: borgbackup
    state: present
    update_cache: true
  register: apt_result
  retries: 3
  until: apt_result is succeeded

- name: Create a local group for borg
  become: true
  group:
    name: "{{ borg_server_group }}"
    system: true

- name: Create a local user for borg
  become: true
  user:
    home: "{{ borg_home_dir }}"
    create_home: true
    comment: Local user for borgbackup server
    name: "{{ borg_server_user }}"
    group: "{{ borg_server_group }}"
    system: true
    # Does not constitute a valid hash, preventing from login via password
    password: "*"
    update_password: always

- name: Create backup directory
  become: true
  file:
    path: "{{ borg_server_backups_dir }}"
    state: directory
    owner: "{{ borg_server_user }}"
    group: "{{ borg_server_group }}"
    mode: u=rwx,g=,o=
...