# Design: Live Config Profile Refresh

## Canonical working copies

Each non-Git Config Profile owns canonical host-side storage. Directory mounts use canonical profile directories; each top-level profile file uses a canonical host file bind-mounted under the container working directory. All compatible instances selected for the profile mount the same sources, so UI and container edits are immediately shared.

## Container compatibility

Supported built-in tools standardize on one non-root user/group. Existing instances retain their current image/user and report `restart_required`. Custom tools are not rewritten; tools that do not opt into the shared user/group return `incompatible_permissions`.

## Save behavior

A profile save writes canonical profile files atomically per file. The save response reports affected compatible instances, `restart_required` topology/runtime changes, `incompatible_permissions`, and detectable overwrite warnings. Last writer wins; no merge or lock protocol is imposed.

## Scope boundaries

Git mount mutation is explicitly deferred. Workspace/repository mounts are never changed. Profile deletion is rejected while running instances still use the profile.
