rfc5228
There are 2 repositories under rfc5228 topic.
ProtonMail/libsieve-php
libsieve-php is a library to manage and modify sieve (RFC5228) scripts. It contains a parser for the sieve language (including extensions) and a client for the managesieve protocol. It is written entirely in PHP 8+.
cypht-org/php-sieve-manager
A modern (started in 2022) PHP library for the ManageSieve protocol (RFC5804) to create/edit Sieve scripts (RFC5228)