1error:2 … while evaluating a branch condition3 at «string»:25:5:4 24| v:5 25| if !builtins.isAttrs v || isDrv v then6 | ^7 26| v89 … in the left operand of the OR (||) operator10 at «string»:25:28:11 24| v:12 25| if !builtins.isAttrs v || isDrv v then13 | ^14 26| v1516 … while evaluating definitions from `/nix/store/lrxvs4l9bqbgjfz7w9bkfg5zqq442jxc-source/modules/transposition.nix':1718 … while evaluating the option `perSystem.x86_64-darwin.checks':1920 … while evaluating definitions from `/nix/store/fk9qzizlr0d3l2sp6g8xnazqlwaqd49c-source/flake.nix, via option perSystem':2122 … while evaluating the module argument `pkgs' in ":anon-11:anon-1":2324 … noting that argument `pkgs` is not externally provided, so querying `_module.args` instead, requiring `config`2526 … while evaluating definitions from `/nix/store/lrxvs4l9bqbgjfz7w9bkfg5zqq442jxc-source/modules/transposition.nix':2728 (stack trace truncated; use '--show-trace' to show the full, detailed trace)2930 error: Nixpkgs 26.11 has dropped support for x86_64-darwin.3132 The 26.05 stable branch still supports x86_64-darwin, and will33 receive security fixes until the end of 2026. If you use channels,34 you can switch to 26.05 as follows:3536 $ sudo nix-channel --add https://nixos.org/channels/nixpkgs-26.05-darwin nixpkgs37 $ sudo nix-channel --update3839 If this doesn’t work, you may need to run:4041 # Lack of sudo is deliberate:42 $ nix-channel --remove nixpkgs4344 If you use flakes, switch your flake input:4546 inputs.nixpkgs = {47 url = "github:NixOS/nixpkgs/nixpkgs-26.05-darwin";48 };4950 See the release notes for more information and alternatives:5152 https://nixos.org/manual/nixpkgs/unstable/release-notes#x86_64-darwin-26.11