public static function init() {

		foreach ( self::$post_types as $post_type ) {

			$unprefixed = self::strip_prefix( $post_type );

			add_action( "llms_user_earned_{$unprefixed}", array( __CLASS__, 'on_earn' ), 20, 2 );
			add_action( "save_post_{$post_type}", array( __CLASS__, 'on_save' ), 20 );

		}

		add_action( 'rest_after_insert_llms_my_certificate', array( __CLASS__, 'on_rest_insert' ), 20, 3 );

	}