assuming that nix-channel tool is in use (from configuration.nix file), nix-channel --add https://channels.nixos.org/nixos-unstable nixpkgs && nixos-rebuild switch --upgrade (from nixos manual https://nixos.org/manual/nixos/stable/#:~:text=And%20if%20you%20want%20to%20live%20on%20the%20bleeding%20edge)

the catch of nixos-unstable is that breaking changes can occur at any time and updating nixos-unstable channel is like upgrading stable to next stable, with less breaking changes, but more frequent. whether this is an acceptable improvement is up to user, and sticking to nixos-stable is a good option

hi all, i'm trying to enable remote builders in my shared config, and one of the machines have itself listed as a builder in its config, so i see duplicate builders in nom's output, and this shows up in journalctl

Mar 11 15:32:55 onion nixos-upgrade-start[3185]: cannot build on 'ssh-ng://nixremote@otto.flippo.cc?port=2200': error: cannot open connection to remote store 'ssh-ng://nixremote@otto.flippo.cc': error: read failed: Connection reset by peer: Host key verification failed.

is there a way to avoid this without specifying the list of builders per-machine? thanks

      buildMachines = [
        {
          # onion
          hostName = "otto.flippo.cc?port=2200";
          protocol = "ssh-ng";
          systems = ["x86_64-linux"];
          sshUser = "nixremote";
          sshKey = "/etc/ssh/ssh_host_ed25519_key";
          maxJobs = 32;
          speedFactor = 10;
        }
        # others omitted
      ];

for reference, this is what i'm doing now

      buildMachines = let
        machine = host:
          lib.mkIf
          (config.networking.hostName or null != host);
      in [
        (machine "onion" {
          hostName = "otto.flippo.cc?port=2200";
          protocol = "ssh-ng";
          systems = ["x86_64-linux"];
          sshUser = "nixremote";
          sshKey = "/etc/ssh/ssh_host_ed25519_key";
          maxJobs = 32;
          speedFactor = 10;
        })
      ];