Hi Ben, sorry for taking so long to respond. It seems, there has been an upstream change, that fixed the issue.

The error was this one:

Local evaluation for computing rebuilds
$ nix-env --extra-experimental-features no-url-literals --option system aarch64-darwin -f <nixpkgs> --nix-path nixpkgs=/Users/edean/.cache/nixpkgs-review/pr-459527-1/nixpkgs nixpkgs-overlays=/private/tmp/nix-shell-1673-462192242/tmpa3pj3v9z -qaP --xml --out-path --show-trace --no-allow-import-from-derivation
error:
       … while querying the derivation named 'flutter-wrapped-3.29.3-sdk-links'

       … 

       error: attribute 'macos-arm64' missing
       at /Users/edean/.cache/nixpkgs-review/pr-459527-1/nixpkgs/pkgs/development/compilers/flutter/engine/tools.nix:56:22:
           55|               url = "https://chrome-infra-packages.appspot.com/client?platform=${stdenv-constants.platform}&version=git_revision:${cipdCommit}";;
           56|               hash = cipdHashes.${stdenv-constants.platform};
             |                      ^
           57|             };
       Did you mean mac-arm64?
https://github.com/NixOS/nixpkgs/pull/459527 failed to build: Failed to list packages: nix-env failed with exit code 1

This Commit seems to have fixed the error. https://github.com/NixOS/nixpkgs/commit/78959ee6e3db1762024c4f8068cc9db57b8d5a6e#diff-a02d8cf7491f5e3faf1245b0bce2bad970c5924fd4b67e954d04cef7ee13147e

I still have no idea, why it wasn't broken for others, anyway...

Hi Ben, sorry for taking so long to respond. It seems, there has been an upstream change, that fixed the issue.

The error was this one:

Local evaluation for computing rebuilds
$ nix-env --extra-experimental-features no-url-literals --option system aarch64-darwin -f <nixpkgs> --nix-path nixpkgs=/Users/edean/.cache/nixpkgs-review/pr-459527-1/nixpkgs nixpkgs-overlays=/private/tmp/nix-shell-1673-462192242/tmpa3pj3v9z -qaP --xml --out-path --show-trace --no-allow-import-from-derivation
error:
       … while querying the derivation named 'flutter-wrapped-3.29.3-sdk-links'

       ……… 

       error: attribute 'macos-arm64' missing
       at /Users/edean/.cache/nixpkgs-review/pr-459527-1/nixpkgs/pkgs/development/compilers/flutter/engine/tools.nix:56:22:
           55|               url = "https://chrome-infra-packages.appspot.com/client?platform=${stdenv-constants.platform}&version=git_revision:${cipdCommit}";;
           56|               hash = cipdHashes.${stdenv-constants.platform};
             |                      ^
           57|             };
       Did you mean mac-arm64?
https://github.com/NixOS/nixpkgs/pull/459527 failed to build: Failed to list packages: nix-env failed with exit code 1

This Commit seems to have fixed the error. https://github.com/NixOS/nixpkgs/commit/78959ee6e3db1762024c4f8068cc9db57b8d5a6e#diff-a02d8cf7491f5e3faf1245b0bce2bad970c5924fd4b67e954d04cef7ee13147e

I still have no idea, why it wasn't broken for others, anyway...

python is possibly broken

       > python3.13(9980,0x1fba16240) malloc: *** error for object 0x103902de0: pointer being freed was not allocated
       > python3.13(9980,0x1fba16240) malloc: *** set a breakpoint in malloc_error_break to debug

https://github.com/NixOS/nixpkgs/issues/461396

So I use the nix.linux-builder for building aarch64-linux dependencies. But I am running into an issue on remote machines not trusting the generated paths since they are untrusted.

Even on my local machine, nix store verify --all is showing they are untrusted:

# nix store verify --all
...
path '/nix/store/0mapnivw6b3678v1b336j9dfxwjhmwc5-unit-dhcpcd.service' is untrusted
path '/nix/store/wy485gdjl7xwlaq5zz2aq55i3yjxry2b-dhcpcd.conf' is untrusted
path '/nix/store/36yijh6hzrg2r45sydbys92wrlwx5gs6-unit-systemd-fsck-.service' is untrusted
path '/nix/store/sr1pdx59gjbh949ai57lg6nzj19pgrpz-unit-script-network-setup-start' is untrusted
path '/nix/store/1j0930fgfwqgbxl517c08v64fmg0bnij-X-Restart-Triggers-systemd-timesyncd' is untrusted
path '/nix/store/421h6j088bq5q9qakabrsh004v2wgxp2-unit-network-setup.service' is untrusted
...

How do I configure the linux builder to sign the generated files so I can distribute the public key to both my local and remote machines?

this is what i observe with nixos-rebuild-ng

# nixos-rebuild-ng switch --flake .#rpi --ask-sudo-password --sudo --target-host "d@rpi"
[sudo] password for d@rpi:
building the system configuration...
warning: Git tree '/Users/d/.config/nix' is dirty
(d@rpi) Password:
(d@rpi) Password:
copying 6 paths...
copying path '/nix/store/3jrv1qr389dfin65n531zz4zb60pc8s1-nix.conf' to 'ssh://d@rpi'...
error: cannot add path '/nix/store/3jrv1qr389dfin65n531zz4zb60pc8s1-nix.conf' because it lacks a signature by a trusted key
error: unexpected end-of-file
Command 'nix-copy-closure --to d@rpi /nix/store/pjsmcl4633j54l4chsgqzv689kbkcrmi-nixos-system-rpi-25.11.20251005.d7f52a7' returned non-zero exit status 1.

Hey I've been using nix on mac for a while and really enjoy it!

I just got a new mac and trying to follow the guide on installing nix-darwin from https://github.com/nix-darwin/nix-darwin seems to fail.

1. I installed nix using the lix installer
2. I get an error when i try to install nix-darwin

Here is the output if i run the command in step 2 of the README.md:

$ sudo nix run nix-darwin/nix-darwin-25.05#darwin-rebuild -- switch
warning: $HOME ('/Users/tje') is not owned by you, falling back to the one defined in the 'passwd' file ('/var/root')
building the system configuration...
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels' does not exist, ignoring
error: file 'darwin' was not found in the Nix search path (add it using $NIX_PATH or -I)

This is a fresh macbook and i tried to follow the steps in the README.md so i'm not sure if I did something wrong or if the README is outdated.