# Native credential boundary

This crate is the storage boundary used by the future Linux AppImage shell.
`Settings` writes only `server_address` and `username` to the client
`settings.json`. Session credentials are stored under the Linux kernel
keyring service `trixie.server.session`, scoped by server address and
username. `load_session` returns `None` when the keyring is unavailable;
callers must return to credential entry and must not create a plaintext
fallback.

The crate uses `keyctl` with argument arrays, never a shell command. It does
not log or serialize session values.