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+# Modules That Tiny-Cloud Supports
+
+The `user-data` file is used to configure Alpine linux state at the boot time. It supports a variety of modules that can be used to install packages, configure users and groups, and more. Tiny-cloud supports following modules:
+
+```yaml
+apk:
+  cache: # path to apk cache where /etc/apk/cache link follows
+  repositories: # <map> defines resulted url https://dl-cdn.alpinelinux.org/alpine/edge/community
+    - base_url: # The base usr of the repository ( https://dl-cdn.alpinelinux.org/alpine )
+      version: # (optional) examples: [ 3.16 | 3.21 | edge ]  if not set will be retrieved from the system
+      repos: # <list>
+        - community
+
+user: # <map> Sets default user
+  name: # <string>
+
+users: # <list>
+  # first one become default user
+  - name:
+    homedir:
+    shell:
+    primary_group:
+    gecos: # description for the user
+    system: # [ true | false ] create a system user
+    no_create_home: # [ true | false ] do not create home directory for the user. Default: false
+    lock_passwd: # reset password of the user
+    ssh_authorized_keys: # <list>
+    groups: # <list>
+      - wheel
+      - power
+    doas: # content of the /etc/doas.d/<name> doas file
+
+ssh_authorized_keys: # public key to be authorized as default user
+
+write_files: # <list> Writes content of the file to the system. Can be used to define configuration files.
+  - path: # destination path of the file (required)
+    permissions: # file mode (default 0644)
+    owner: # owner:group of the file (default root:root)
+    encoding: # provided endoding of the file [gzip|gz|gz+base64|gzip+base64|gz+b64|gzip+b64|base64|b64|text/plain] (default text/plain)
+    append: # if "true", then content will be added to the end of the file
+    content: | # (required)
+      here is multiline
+      content of your file
+
+ntp:
+  enabled: # checks for [ yes | true ]. Otherwise do not enables ntp service
+  ntp_client: # [ ntpd | chrony | openntpd ] (default: chrony)
+
+package_update: # if "true" runs `apk update`
+
+package_upgrade: # if "true" runs `apk upgrade`
+
+packages: # <list>
+  - curl
+  - bash
+
+groups: # <list>
+  - wheel
+  - admin
+```