diff --git a/server-command.php b/server-command.php
index 9ad8ad5..3714abb 100644
--- a/server-command.php
+++ b/server-command.php
@@ -9,4 +9,11 @@
 	require_once $autoload;
 }
 
-WP_CLI::add_command( 'server', 'Server_Command', array() );
+WP_CLI::add_command( 'server', 'Server_Command', array(
+	'before_invoke' => function() {
+		$min_version = '5.4';
+		if ( version_compare( PHP_VERSION, $min_version, '<' ) ) {
+			WP_CLI::error( "The `wp server` command requires PHP {$min_version} or newer." );
+		}
+	}
+) );
diff --git a/src/Server_Command.php b/src/Server_Command.php
index 930d416..d13b555 100644
--- a/src/Server_Command.php
+++ b/src/Server_Command.php
@@ -55,11 +55,6 @@ class Server_Command extends WP_CLI_Command {
 	 * @when before_wp_load
 	 */
 	function __invoke( $_, $assoc_args ) {
-		$min_version = '5.4';
-		if ( version_compare( PHP_VERSION, $min_version, '<' ) ) {
-			WP_CLI::error( "The `wp server` command requires PHP $min_version or newer." );
-		}
-
 		$defaults = array(
 			'host' => 'localhost',
 			'port' => 8080,