diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..aaa587d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+# Config files:
+/config/*.json
+!/config/pb-dydns.example.json
diff --git a/bin/pb-dydns.php b/bin/pb-dydns.php
index f8d1e59..2612956 100755
--- a/bin/pb-dydns.php
+++ b/bin/pb-dydns.php
@@ -1,144 +1,13 @@
+#!/usr/bin/env php
 <?php
 
-//
-// This script updates the DNS type A on porkbun.com so it is always pointing to your public IP address.
-//
-// Dependencies:
-//
-// - PorkbunAPI.php
-// - pb-dydns.json (it will be created automatically the 1st time)
-//
-// How to use it:
-//
-// - from command line:
-//
-// $ php /path/to/pb-dydns.php domain_name
-//
-// It will retrieve all DNS records for the specificied domain_name and update the A type ones
-// with your public IP address.
-//
-//- as a cron job, to add it to:
-//
-// $ crontab -e
-//
-// Append this line as many times as domains you want to automatically update:
-//
-// */10 * * * *	php /path/to/pb-dydns.php domain_name > /dev/null
-//
-// And restart cron (I'm not sure if this is necessary):
-//
-// $ sudo systemctl restart cron
-//
-// Entries to a log file called "pb-dydns.log" will be added, to view it you can:
-//
-// $ cat /path/to/pb-dydns.log
-//
+require __DIR__ . "/PorkbunAPI.php";
+require __DIR__ . "/Config.php";
+require __DIR__ . "/Logger.php";
+require __DIR__ . "/UpdateDnsCommand.php";
 
-require "PorkbunAPI.php";
+$config = new Config(__DIR__ . "/pb-dydns.json");
+$logger = new Logger(__DIR__ . "/pb-dydns.log");
 
-// Make sure that pb-dydns.json exists:
-$config_filename = __DIR__ . "/pb-dydns.json";
-
-if (!file_exists($config_filename))
-{
-	echo "The config file $config_filename does not exist." . PHP_EOL;
-
-	$config = json_encode(array
-	(
-		"url" => "https://porkbun.com/api/json/v3/",
-		"apikey" => "",
-		"secretapikey" => ""
-	), JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);
-
-	file_put_contents($config_filename, $config);
-
-	echo "It has been created but you must edit it with your API key and secret." . PHP_EOL;
-	echo "After that you can try again." . PHP_EOL;
-
-	exit(1);
-}
-
-// Domain name must be provided as argument.
-// There should be 2 arguments as $argc includes the script name itself:
-if ($argc != 2)
-{
-	echo_to_cli("This script requires a domain name as argument:" . PHP_EOL);
-	echo_to_cli("php $argv[0] domain_name" . PHP_EOL);
-
-	exit(2);
-}
-
-// Take the arguments in individual variables:
-$myDomain = $argv[1];
-
-// Create an instance of PorkbunAPI:
-$pbapi = new PorkbunAPI($config_filename);
-
-// Test connection to Porkbun API in order to get the public IP:
-$raw = $pbapi->ping();
-$result = json_decode($raw);
-
-if ($result === null)
-{
-	echo_to_cli("Invalid JSON returned by Porkbun API:\n$raw\n");
-	exit(3);
-}
-
-if (!isset($result->status))
-{
-	echo_to_cli("Porkbun API response missing 'status' field:\n$raw\n");
-	exit(3);
-}
-
-if ($result->status !== "SUCCESS") 
-{
-	echo_to_cli("Porkbun API returned an error:\n$raw\n");
-	exit(3);
-}
-
-if (!isset($result->yourIp))
-{
-	echo_to_cli("Porkbun API did not return your public IP.\n");
-	exit(3);
-}
-
-$myIp = $result->yourIp;
-
-echo_to_cli("Your public IP address is $myIp" . PHP_EOL);
-
-// Retrieve all DNS records associated with user's domain:
-$records = $pbapi->retrieve($myDomain);
-
-// Discard those records that are not type "A":
-$data = json_decode($records);
-$filteredRecords = array_filter($data->records, function ($record)
-{
-	return $record->type == "A";
-});
-
-$log_filename = __DIR__ . "/pb-dydns.log";
-
-// Update the records that passed the filter with the public IP:
-foreach ($filteredRecords as $record)
-{
-	echo_to_cli("Porkbun's DNS for $record->name is pointing to $record->content... ");
-
-	if ($record->content != $myIp)
-	{
-		echo_to_cli("Let's change that... ");
-		$name = rtrim(strstr($record->name, $myDomain, true), ".");
-		$result = json_decode($pbapi->edit($myDomain, $record->id, $myIp, $name));
-		if ($result->status == "SUCCESS") echo_to_cli("Done!" . PHP_EOL);
-
-		$now = date('Y-m-d H:i:s');
-		$message = "$now: Updated DNS on $record->name from $record->content to $myIp" . PHP_EOL;
-		file_put_contents($log_filename, $message, FILE_APPEND);
-	}
-
-	else
-	{
-		echo_to_cli("Nothing needs to be changed!" . PHP_EOL);
-	}
-}
-
-?>
+$cmd = new UpdateDnsCommand($config, $logger);
+$cmd->run($argv);
diff --git a/config/pb-dydns.example.json b/config/pb-dydns.example.json
new file mode 100644
index 0000000..a5e11d8
--- /dev/null
+++ b/config/pb-dydns.example.json
@@ -0,0 +1,5 @@
+{
+	"url": "https://api.porkbun.com/api/json/v3/",
+	"apikey": "YOUR_API_KEY_HERE",
+	"secretapikey": "YOUR_SECRET_KEY_HERE"
+}
diff --git a/src/Api/PorkbunAPI.php b/src/Api/PorkbunAPI.php
index 2e4fcc3..1f3e4cb 100644
--- a/src/Api/PorkbunAPI.php
+++ b/src/Api/PorkbunAPI.php
@@ -1,29 +1,16 @@
 <?php
 
-//
-// Outputs a message to CLI, if this script is run from CLI.
-//
-
-function echo_to_cli(string $message)
-{
-	if (php_sapi_name() === 'cli') echo $message;
-}
-
 //
 // Wrapper class to communicate with Porkbun API.
 //
 
 class PorkbunAPI
 {
+	private stdClass $config;
+
 	function __construct(string $config_filename)
 	{
 		$this->config = json_decode(file_get_contents($config_filename));
-		$this->ch = curl_init();
-	}
-
-	function __destruct()
-	{
-		curl_close($this->ch);
 	}
 
 	//
@@ -37,15 +24,17 @@ class PorkbunAPI
 		// Create the correct endpoint based on the URL:
 		$endpoint = $this->config->url . "ping";
 
+		$ch = curl_init();
+
 		// Set some cURL options:
-		curl_setopt($this->ch, CURLOPT_URL, $endpoint);
-		curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, 1);
-		curl_setopt($this->ch, CURLOPT_POST, 1);
+		curl_setopt($ch, CURLOPT_URL, $endpoint);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
+		curl_setopt($ch, CURLOPT_POST, 1);
 
 		// Tell the server that the request body contains JSON data:
 		$headers = array();
 		$headers[] = "Content-Type: application/json";
-		curl_setopt($this->ch, CURLOPT_HTTPHEADER, $headers);
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
 
 		// Porkbun API wants to be passed data in JSON format:
 		$json = array
@@ -54,13 +43,13 @@ class PorkbunAPI
 			"secretapikey" => $this->config->secretapikey
 		);
 
-		curl_setopt($this->ch, CURLOPT_POSTFIELDS, json_encode($json));
+		curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($json));
 
 		// Execute cURL and return the result:
-		$result = curl_exec($this->ch);
-		if (curl_errno($this->ch))
+		$result = curl_exec($ch);
+		if (curl_errno($ch))
 		{
-			echo_to_cli("Error: " . curl_error($this->ch));
+			Console::echo("Error: " . curl_error($ch));
 			exit;
 		}
 
@@ -78,15 +67,17 @@ class PorkbunAPI
 		// Create the correct endpoint based on the URL:
 		$endpoint = $this->config->url . "dns/create/" . $domain;
 
+		$ch = curl_init();
+
 		// Set some cURL options:
-		curl_setopt($this->ch, CURLOPT_URL, $endpoint);
-		curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, 1);
-		curl_setopt($this->ch, CURLOPT_POST, 1);
+		curl_setopt($ch, CURLOPT_URL, $endpoint);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
+		curl_setopt($ch, CURLOPT_POST, 1);
 
 		// Tell the server that the request body contains JSON data:
 		$headers = array();
 		$headers[] = "Content-Type: application/json";
-		curl_setopt($this->ch, CURLOPT_HTTPHEADER, $headers);
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
 
 		// Porkbun API wants to be passed data in JSON format:
 		$json = array
@@ -99,13 +90,13 @@ class PorkbunAPI
 			"ttl" => "$ttl"
 		);
 
-		curl_setopt($this->ch, CURLOPT_POSTFIELDS, json_encode($json));
+		curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($json));
 
 		// Execute cURL and return the result:
-		$result = curl_exec($this->ch);
-		if (curl_errno($this->ch))
+		$result = curl_exec($ch);
+		if (curl_errno($ch))
 		{
-			echo_to_cli("Error: " . curl_error($this->ch));
+			Console::echo("Error: " . curl_error($ch));
 			exit;
 		}
 
@@ -124,15 +115,17 @@ class PorkbunAPI
 		$endpoint = $this->config->url . "dns/edit/" . $domain;
 		$endpoint .= "/" . $id;
 
+		$ch = curl_init();
+
 		// Set some cURL options:
-		curl_setopt($this->ch, CURLOPT_URL, $endpoint);
-		curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, 1);
-		curl_setopt($this->ch, CURLOPT_POST, 1);
+		curl_setopt($ch, CURLOPT_URL, $endpoint);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
+		curl_setopt($ch, CURLOPT_POST, 1);
 
 		// Tell the server that the request body contains JSON data:
 		$headers = array();
 		$headers[] = "Content-Type: application/json";
-		curl_setopt($this->ch, CURLOPT_HTTPHEADER, $headers);
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
 
 		// Porkbun API wants the API key and secret in a JSON structure:
 		$json = array
@@ -144,13 +137,13 @@ class PorkbunAPI
 			"content" => "$content"
 		);
 
-		curl_setopt($this->ch, CURLOPT_POSTFIELDS, json_encode($json));
+		curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($json));
 
 		// Execute cURL and return the result:
-		$result = curl_exec($this->ch);
-		if (curl_errno($this->ch))
+		$result = curl_exec($ch);
+		if (curl_errno($ch))
 		{
-			echo_to_cli("Error: " . curl_error($this->ch));
+			Console::echo("Error: " . curl_error($ch));
 			exit;
 		}
 
@@ -163,21 +156,23 @@ class PorkbunAPI
 	// https://porkbun.com/api/json/v3/documentation#DNS%20Retrieve%20Records%20by%20Domain%20or%20ID
 	//
 
-	function retrieve(string $domain, string $id = null)
+	function retrieve(string $domain, ?string $id = null)
 	{
 		// Create the correct endpoint based on the URL:
 		$endpoint = $this->config->url . "dns/retrieve/" . $domain;
 		if (!is_null($id)) $endpoint .= "/" . $id;
 
+		$ch = curl_init();
+
 		// Set some cURL options:
-		curl_setopt($this->ch, CURLOPT_URL, $endpoint);
-		curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, 1);
-		curl_setopt($this->ch, CURLOPT_POST, 1);
+		curl_setopt($ch, CURLOPT_URL, $endpoint);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
+		curl_setopt($ch, CURLOPT_POST, 1);
 
 		// Tell the server that the request body contains JSON data:
 		$headers = array();
 		$headers[] = "Content-Type: application/json";
-		curl_setopt($this->ch, CURLOPT_HTTPHEADER, $headers);
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
 
 		// Porkbun API wants the API key and secret in a JSON structure:
 		$json = array
@@ -186,13 +181,13 @@ class PorkbunAPI
 			"secretapikey" => $this->config->secretapikey
 		);
 
-		curl_setopt($this->ch, CURLOPT_POSTFIELDS, json_encode($json));
+		curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($json));
 
 		// Execute cURL and return the result:
-		$result = curl_exec($this->ch);
-		if (curl_errno($this->ch))
+		$result = curl_exec($ch);
+		if (curl_errno($ch))
 		{
-			echo_to_cli("Error: " . curl_error($this->ch));
+			Console::echo("Error: " . curl_error($ch));
 			exit;
 		}
 
@@ -205,21 +200,23 @@ class PorkbunAPI
 	// https://porkbun.com/api/json/v3/documentation#DNS%20Retrieve%20Records%20by%20Domain,%20Subdomain%20and%20Type
 	//
 
-	function retrieveByNameType(string $domain, string $type, string $subdomain = null)
+	function retrieveByNameType(string $domain, string $type, ?string $subdomain = null)
 	{
 		// Create the correct endpoint based on the URL:
 		$endpoint = $this->config->url . "dns/retrieveByNameType/" . $domain . "/" . $type;
 		if (!is_null($subdomain)) $endpoint .= "/" . $subdomain;
 
+		$ch = curl_init();
+
 		// Set some cURL options:
-		curl_setopt($this->ch, CURLOPT_URL, $endpoint);
-		curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, 1);
-		curl_setopt($this->ch, CURLOPT_POST, 1);
+		curl_setopt($ch, CURLOPT_URL, $endpoint);
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
+		curl_setopt($ch, CURLOPT_POST, 1);
 
 		// Tell the server that the request body contains JSON data:
 		$headers = array();
 		$headers[] = "Content-Type: application/json";
-		curl_setopt($this->ch, CURLOPT_HTTPHEADER, $headers);
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
 
 		// Porkbun API wants the API key and secret in a JSON structure:
 		$json = array
@@ -228,22 +225,18 @@ class PorkbunAPI
 			"secretapikey" => $this->config->secretapikey
 		);
 
-		curl_setopt($this->ch, CURLOPT_POSTFIELDS, json_encode($json));
+		curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($json));
 
 		// Execute cURL and return the result:
-		$result = curl_exec($this->ch);
-		if (curl_errno($this->ch))
+		$result = curl_exec($ch);
+		if (curl_errno($ch))
 		{
-			echo_to_cli("Error: " . curl_error($this->ch));
+			Console::echo("Error: " . curl_error($ch));
 			exit;
 		}
 
 		return $result;
 	}
-	
-	// These properties don't need to be declared as they would be dynamically created when assigned a value:
-	private stdClass $config;
-	private CurlHandle $ch;
 };
 
 ?>
diff --git a/src/Command/.gitkeep b/src/Command/.gitkeep
deleted file mode 100644
index e69de29..0000000
diff --git a/src/Command/UpdateDnsCommand.php b/src/Command/UpdateDnsCommand.php
new file mode 100644
index 0000000..fc37ecd
--- /dev/null
+++ b/src/Command/UpdateDnsCommand.php
@@ -0,0 +1,94 @@
+<?php
+
+require_once __DIR__ . '/../Api/PorkbunAPI.php';
+require_once __DIR__ . '/../Config/Config.php';
+require_once __DIR__ . '/../Util/Logger.php';
+require_once __DIR__ . '/../Util/Console.php';
+
+class UpdateDnsCommand
+{
+	private Config $config;
+	private Logger $logger;
+
+	public function __construct(Config $config, Logger $logger)
+	{
+		$this->config = $config;
+		$this->logger = $logger;
+	}
+
+	public function run(array $argv): void
+	{
+		if (count($argv) < 2)
+		{
+			echo "Usage: pb-dydns.php <domain>\n";
+			exit(1);
+		}
+
+		$domain = $argv[1];
+
+		$api = new PorkbunAPI($this->config->get('config_filename'));
+
+		// Test connection to Porkbun API in order to get the public IP:
+		$raw = $api->ping();
+		$result = json_decode($raw);
+
+		if ($result === null)
+		{
+			Console::echo("Invalid JSON returned by Porkbun API:\n$raw\n");
+			exit(3);
+		}
+
+		if (!isset($result->status))
+		{
+			Console::echo("Porkbun API response missing 'status' field:\n$raw\n");
+			exit(3);
+		}
+
+		if ($result->status !== "SUCCESS") 
+		{
+			Console::echo("Porkbun API returned an error:\n$raw\n");
+			exit(3);
+		}
+
+		if (!isset($result->yourIp))
+		{
+			Console::echo("Porkbun API did not return your public IP.\n");
+			exit(3);
+		}
+
+		$myIp = $result->yourIp;
+
+		Console::echo("Your public IP address is $myIp" . PHP_EOL);
+
+		// Retrieve all DNS records associated with user's domain:
+		$records = $api->retrieve($domain);
+
+		// Discard those records that are not type "A":
+		$data = json_decode($records);
+		$filteredRecords = array_filter($data->records, function ($record)
+		{
+			return $record->type == "A";
+		});
+
+		// Update the records that passed the filter with the public IP:
+		foreach ($filteredRecords as $record)
+		{
+			Console::echo("Porkbun's DNS for $record->name is pointing to $record->content... ");
+
+			if ($record->content != $myIp)
+			{
+				Console::echo("Let's change that... ");
+				$name = rtrim(strstr($record->name, $domain, true), ".");
+				$result = json_decode($api->edit($domain, $record->id, $myIp, $name));
+				if ($result->status == "SUCCESS") Console::echo("Done!" . PHP_EOL);
+
+				$this->logger->log("Updated DNS on $record->name from $record->content to $myIp");
+			}
+
+			else
+			{
+				Console::echo("Nothing needs to be changed!" . PHP_EOL);
+			}
+		}
+	}
+}
diff --git a/src/Config/.gitkeep b/src/Config/.gitkeep
deleted file mode 100644
index e69de29..0000000
diff --git a/src/Config/Config.php b/src/Config/Config.php
new file mode 100644
index 0000000..0c14b81
--- /dev/null
+++ b/src/Config/Config.php
@@ -0,0 +1,27 @@
+<?php
+
+class Config
+{
+	private array $data;
+
+	public function __construct(string $filename)
+	{
+		if (!file_exists($filename))
+		{
+			throw new RuntimeException("Config file not found: $filename");
+		}
+
+		$json = file_get_contents($filename);
+		$this->data = json_decode($json, true);
+
+		if ($this->data === null)
+		{
+			throw new RuntimeException("Invalid JSON in config file: $filename");
+		}
+	}
+
+	public function get(string $key): mixed
+	{
+		return $this->data[$key] ?? null;
+	}
+}
diff --git a/src/Util/.gitkeep b/src/Util/.gitkeep
deleted file mode 100644
index e69de29..0000000
diff --git a/src/Util/Console.php b/src/Util/Console.php
new file mode 100644
index 0000000..dcf667e
--- /dev/null
+++ b/src/Util/Console.php
@@ -0,0 +1,9 @@
+<?php
+
+class Console
+{
+	public static function echo(string $message): void
+	{
+		fwrite(STDOUT, $message . PHP_EOL);
+	}
+}
diff --git a/src/Util/Logger.php b/src/Util/Logger.php
new file mode 100644
index 0000000..317b220
--- /dev/null
+++ b/src/Util/Logger.php
@@ -0,0 +1,17 @@
+<?php
+
+class Logger
+{
+	private string $filename;
+
+	public function __construct(string $filename)
+	{
+		$this->filename = $filename;
+	}
+
+	public function log(string $message): void
+	{
+		$timestamp = date("Y-m-d H:i:s");
+		file_put_contents($this->filename, $timestamp . ' ' . $message . PHP_EOL, FILE_APPEND);
+	}
+}