By mirrored repository, I am referring to the ability to have a local and cloud repository and perform a snapshot to both destinations simultaneously.
It seems there could be significant opportunities for performance efficiencies and cache size if a single snapshot could be sent to multiple repositories. Kopia would only need to hash and compress the source files only once, before saving to both repositories, and there could be a shared cache.
I understand that there might be issues if the repositories diverge, so maybe there could be safeguards for that possibility. Maybe the repository configuration could reference a ‘mirrored’ pair and bring the repositories into sync before performing the snapshot.