to expand on my thoughts, indeed, binary cache means so many things, I think what would be interesting is:

• nix has interesting and strong store backends: filesystem, S3, etc.

• each one of them can be exposed on a reasonable protocol (HTTP/3, etc. whatever) using nix itself

• nix can handle certain operations by itself which are reasonable: signing store paths (via PKCS#11 or local signing stuff), etc.

• deduplication should be fundamental & baked-in

• multi-tenancy should ideally be just multiple nix stores (maybe they can share blocks or something whatever)

• you can bring your own reverse proxy for auth, authnz based on your "usecase" logic

• etc.

In reply to @samrose:matrix.org
If there is anything people can do to help that are not part of the core team, please let us know.