This is an implementation of the OpenBSD Blowfish password hashing algorithm, as described in "A Future-Adaptable Password Scheme" by Niels Provos and David Mazieres. It's core is based on jBcrypt, ...
OpenAI has recently published a detailed architecture description of the Codex App Server, a bidirectional protocol that decouples the Codex coding agent's core logic from its various client surfaces.