D-Bus being the standard IPC system of the Linux desktop. This implementation would basically set linux at an OS platform level to support ctap2/Fido u2f, currently there is only application level support via Firefox. Not sure why its the readme.md refers to webauthn when it's ctap2. Lots of confusing acronyms

If you're in the mood for some IAM reading, Awesome IAM is a comprehensive compendium of authentication and authorization resources for developers: https://github.com/kdeldycke/awesome-iam