Acme PHP Core is the core of the Acme PHP project : it is a basis for the others more high-level repositories. It consists of a raw implementation of the Let's Encrypt ACME protocol.
If you want to chat with us or have questions, ping @tgalopin or @jderusse on the Symfony Slack!
You usually will want to use either the Acme PHP CLI client or an implementation for your application framework.
However, in some cases, you may want to manage SSL certificates directly from your application. In these cases, this library will be useful to you.
Acme PHP Core does nothing more than implementing the Let's Encrypt/ACME protocol : the generated SSL keys and certificates are stored in memory and returned to your script. You are the one in charge of storing them somewhere persistent.
Read the official Acme PHP documentation.
The Acme PHP test suite is located in the main repository: https://github.com/acmephp/acmephp#launch-the-test-suite.