2023-12-01 Nix team meeting minutes #108

Attendees: @Ericson2314 @thufschmitt @edolstra @tomberek @roberth


  • Triage
  • Hydra status


extra-* settings are order depedendent: extra-foo option is a noop if used before foo in the configuration file · Issue #9487 · NixOS/nix · GitHub

  • @edolstra: We could warn in that case
  • Agreement

bug: nix commands do not follow flake-url symlinks · Issue #9463 · NixOS/nix · GitHub

  • Confirmed it’s a bug (but low-prio). Contributions welcome

Non-flake file input records recursive hash in `flake.lock` but using flat hash in store path (mismatched hash mode) · Issue #9456 · NixOS/nix · GitHub

  • Indeed wrong. The recursive hash should be used everywhere
  • Fixing it is a breaking change, but one we can afford
  • Assigned to @edolstra

Improve testing infra for fetchTree/fetchGit · Issue #9388 · NixOS/nix · GitHub

  • Clear improvement. Contributions welcome

Hydra status

  • @ericson2314 clearing his backlog, and the CA stuff in hydra that @thufschmitt wrote is still lying dead there (https://github.com/NixOS/hydra/pull/1313).

    • Partially concurrent draft PR by Eelco to use the store abstraction instead
    • @ericson2314: starting by splitting stuff is slightly more work, but better in the long run
  • @thufschmitt: More broadly, there’s a maintenance problem on Hydra

  • Problem: Hydra is critical and hard to approach, so discourages contributions and makes maintenance harder

    • @tomberek: Having a staging hydra could help a lot with that
    • Could be used to build nixpkgs staging?
      • Interesting because having a separate infra for staging might be a useful thing on its own
      • The staging people might not want to depend on unstable infra though
    • hydra.ngi0.nixos.org could be repurposed for that
      • @edolstra and @thufschmitt have root access. Can give @tomberek root access
      • Deployed with nixos-rebuild targeting ~/nixos-org-configurations/ngi0/makemake
      • @tomberek will ask the infra team to create a builder and set things up
    • stable branch for hydra
  • 526e8bd actually the NGI hydra already is off a CA derivations branch

    • conclusion: that’s OK. We don’t need to worry about CA then. When it is merged to master, it will be tested here again, but we can live with the “regression” from switching from that PR branch in the meantime.
  • NGI can go to master immediately

  • Nix bumping PRs can be merged

  • @Ericson2314 TODO: PR describing deployment process?


  • @thufschmitt: We could have a team talk there
  • Broad agreement, @thufschmitt will try to come up with a proposal before the deadline

Great to see there’s some discussion about hydra maintenance. Hope we can get to a solution there somehow.