mara via triage on #619 (post-merge follow-up):
> "I thought all nixpkgs follow the one hyperhive was deployed
> with?! if not, thats what we should fix."
This is the fix. Flip the rendered meta flake from:
nixpkgs.url = "github:NixOS/nixpkgs/nixos-26.05";
nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
hyperhive.url = "...";
hyperhive.inputs.nixpkgs.follows = "nixpkgs";
hyperhive.inputs.nixpkgs-unstable.follows = "nixpkgs-unstable";
to:
hyperhive.url = "...";
nixpkgs.follows = "hyperhive/nixpkgs";
nixpkgs-unstable.follows = "hyperhive/nixpkgs-unstable";
Net effect: hyperhive's `flake.nix` is the single channel-pin
authority. Operators who want to slide the whole swarm onto a
different channel do it at the host level via
`inputs.hyperhive.inputs.nixpkgs.follows = "nixpkgs"`, which makes
hyperhive's nixpkgs = the host's nixpkgs and cascades through every
agent transparently.
This is the same shape I shipped in #619 v1 (then reverted per mara
on comment 7354, then re-affirmed via triage). Going with the
re-affirmed direction.
Closes#317 invariant still satisfied — `nixpkgs` is a single
canonical name in the meta tree, just resolving through hyperhive
instead of being its own root input.
Tests:
- rename `render_flake_declares_canonical_nixpkgs` →
`render_flake_aliases_nixpkgs_to_hyperhive`, asserts the new
follows-form AND the absence of any literal `nixpkgs.url`
- drop `render_flake_collapses_hyperhive_nixpkgs_via_follows` (no
separate meta-level nixpkgs to collapse anymore)