What could cause this flake to fail on my computer and succeed on another?

Help
1

I am running NixOS on WSL

I use nix version nix 2.18.1 I run

 nix develop

in the directory containing flake.nix that looks like that:

{
 description = "Python environment with ollama";

 inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
 inputs.flake-utils.url = "github:numtide/flake-utils";

 outputs = { self, nixpkgs, flake-utils, ... }:
    flake-utils.lib.eachDefaultSystem (system: let
      pkgs = nixpkgs.legacyPackages.${system};
      
      jina-hubble-sdk = with pkgs.python3Packages;
        buildPythonPackage rec {
          pname = "jina-hubble-sdk";
          version = "0.39.0";

          src = pkgs.fetchPypi {
            inherit pname version;
            sha256 = "9021417794a6d3cf3fad8a880cf668a3a986b9d53d5be5fa391aae1767a5b9b0";
          };

          nativeBuildInputs = [
            poetry-core
            pkgs.dos2unix # Add dos2unix to convert line endings
          ];

          propagatedBuildInputs = [
            pep517
            pip
            requests
            aiohttp
            rich
            importlib-metadata
            filelock
            pathspec
            docker
            pyyaml
            python-jose
          ];
          

          # Convert line endings to Unix-style
          preConfigure = ''
            export HOME=$(mktemp -d)
          '';
             # put this code inside preConfigure if you want to run it dos2unix -f /nix/store/v099hqvw5z87423p4hz1vfhzaqa07dii-stdenv-linux/setup
        };
   
      pythonEnv = pkgs:
        pkgs.python3.withPackages (ps:
          with ps; [
             jina-hubble-sdk
          ]);
    in {
      devShells.default = pkgs.mkShell {
        buildInputs = with pkgs; [
          curl
          ollama
          (pythonEnv pkgs)
        ];
      };
    });
}

and I get the following error

error: builder for ‘/nix/store/dm6cxw020s7whbfgqj8jivd3dv1pby0i-python3.11-jina-hubble-sdk-0.39.0.drv’ failed with exit code 127; last 10 log lines: > Using setuptoolsCheckPhase > Running phase: unpackPhase > unpacking source archive /nix/store/9q6b5l6955sabgvk8ah5xx0sfji25zmn-jina-hubble-sdk-0.39.0.tar.gz > source root is jina-hubble-sdk-0.39.0 > setting SOURCE_DATE_EPOCH to timestamp 1688549032 of file jina-hubble-sdk-0.39.0/setup.cfg > Running phase: patchPhase > Running phase: updateAutotoolsGnuConfigScriptsPhase > Running phase: configurePhase > /nix/store/v099hqvw5z87423p4hz1vfhzaqa07dii-stdenv-linux/setup: line 114: $‘\r’: command not found > /nix/store/v099hqvw5z87423p4hz1vfhzaqa07dii-stdenv-linux/setup: line 131: pop_var_context: head of shell_variables not a function context For full logs, run ‘nix-store -l /nix/store/dm6cxw020s7whbfgqj8jivd3dv1pby0i-python3.11-jina-hubble-sdk-0.39.0.drv’. error: 1 dependencies of derivation ‘/nix/store/25gl4f29rr56ci1h5k53wmm7wgfmk2p2-python3-3.11.8-env.drv’ failed to build error: 1 dependencies of derivation ‘/nix/store/pxkgnl5nx66fcdi1rkvz86kbfrvlmhn2-nix-shell-env.drv’ failed to build

But when I asked for help on stackoverflow, somebody say that this problem don’t occur on his computer and he is using nixos with WSL too.

nix flake - How to fix Nix build failure due to a file using the windows way to break line - Stack Overflow

Hence my question, why is causing this flake not to run correctly on my computer when it works for others ?

2

Looks like your copy of flake.nix (the file, not the code) is using DOS line endings:

❯ nix shell nixpkgs#toybox
❯ unix2dos ./flake.nix 
❯ nix develop        
error: builder for '/nix/store/bn0gx56rasjhx41kgm5921nk784k8496-python3.11-jina-hubble-sdk-0.39.0.drv' failed with exit code 127;
...
       > /nix/store/v099hqvw5z87423p4hz1vfhzaqa07dii-stdenv-linux/setup: line 114: $'\r': command not found
       > /nix/store/v099hqvw5z87423p4hz1vfhzaqa07dii-stdenv-linux/setup: line 131: pop_var_context: head of shell_variabl
...

❯ dos2unix ./flake.nix  
❯ nix develop

/tmp/tmp.JzhsSBmlx8 via ❄️  impure (nix-shell-env) 
❯
3

I wrote the flake using visual studio code, open from windows. That meant that my flake was coded with dos encoding. I convert my flake with dos2nix and I can run it without problem.
I should have tested earlier but the error message didn’t say that error was coming from my flake and until now I wrote all my falke with dos encoding and it worked.

@ VTimofeenko Thank you for your help

4

My guess is that the it’s preConfigure script that was causing the builder to crash. Maybe previous flakes did not have embedded scripts.

In any case – quick search for dos line endings shows some weird bugs so it’s best to avoid it.