New from our team: A PHP implementation of RFC 9180 (HPKE - Hybrid Public-Key Encryption):
https://github.com/paragonie/hpke-php
This should serve as building block for more secure protocols (i.e., RFC 9420 a.k.a. Messaging Layer Security)/
This would, in turn, enable PHP developers to write software that communicates with MLS-compatible end-to-end encrypted messaging services.