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README.md

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+# DDNS
+
+This application enables automatically updating DNS records for various providers.
+
+## Features
+
+* Automatically detect the current IP.
+    * Both IPv4 and IPv6 are supported.
+    * IP resolution depends on the selected service.
+        * ipify (default)
+* Update DNS records in the selected provider.
+    * Porkbun
+* Native (Linux)
+
+## Build
+
+Execute `./gradlew assemble`.  
+The resulting binary will be located in `./build/bin/releaseExecutable/`.
+
+Removing the extension from the binary and adding it to `/usr/local/bin/` enables the use of `ddns` in the terminal.
+
+## Usage
+
+The following command updates all A and AAAA DNS records in Porkbun for `example.com` and `test.example.com`.
+
+```
+ddns porkbun \ 
+    --key=... \
+    --secret-key=... \
+    --domain=example.com \
+    --subdomain= \
+    --subdomain=test
+```
+
+Optionally, a file can be used to declare one or more configurations.  
+The above example can be declared as follows.
+
+```
+porkbun
+key=...
+secret-key=...
+domain=example.com
+subdomain=
+subdomain=test
+```
+
+To use this config file, execute the command `ddns --config=...`.
+By default, the config file is `/etc/ddns.conf`.
+
+This process can be automated using systemd or cron.