3. BtreeAppend-only B+Tree implemented purely in PHP.
4. JephApplication framework that runs Javascript on top of regular PHP engine
5. BunnyPerformant pure-PHP AMQP (RabbitMQ) sync/async (ReactPHP) library
6. pacc[OLD] use PHP7 rewrite https://github.com/axmachado/pacc (orig. description: pacc (PHP yACC), parser generator for PHP)