[nix] cross-compile cmd/cli using flake.nix.

[c4lliope]

(... a small missing piece.)

largely based on: https://wiki.nixos.org/wiki/Go
depends on: https://github.com/numtide/flake-utils

[c4lliope]

oh, I'm a lil silly. I kept the fetchFromGitHub which I was using for a local build. This should use a normal path. Hold up!

[c4lliope]

Yep. There ya go.

For anyone else, until this is merged, import this module to your home-manager profile:

# railpack.home.nix
{ pkgs, edge, ... }: let
  railpack = pkgs.buildGoModule rec {
    pname = "railpack";
    version = "0.9.0";
    subPackages = [ "cmd/cli" ];
    src = pkgs.fetchFromGitHub {
      owner = "railwayapp";
      repo = "railpack";
      rev = "v${version}";
      sha256 = "sha256-7aXv4g1/Bqovq9JMKpH+wYx2JPeklurnZzQmlMaRUXc=";
    };
    vendorHash = "sha256-bn6GsJBRg4S5IWBShlYXk12nNuAnv4MmKZvxE0sujT8=";
  };
in {
  programs.mise = {
    enable = true;
    # enableNushellIntegration = false;
  };

  home.packages =  with pkgs; [
  (pkgs.writeShellScriptBin "railpack" "exec -a $0 ${railpack}/bin/cli $@")
  ];
}

The one mise line is commented because this clobbered my prior nushell env.nu, see: https://home-manager-options.extranix.com/?query=programs.mise&release=release-25.05

[c4lliope]

huh.... is there an ENV var we can use to pass in the NixOS-packaged mise path?

➜ railpack b .

╭──────────────╮
│ Railpack dev │
╰──────────────╯

  ✖ Failed to ensure mise is installed: failed to validate installation: failed to run version check: exit status 127



❄ calliope@chesapeake:  …/radicale   nix !+?     20:59 

❄ calliope@chesapeake:  …/radicale   nix !+?     20:59 
➜ railpack b .

╭──────────────╮
│ Railpack dev │
╰──────────────╯

  ↳ Detected Python
  ⚠ Failed to get package versions from mise: failed to get package versions: failed to run mise command '/tmp/railpack/mise/mise-2025.10.4 --cd /home/calliope/disc/nvme0n1p6/code/kozea/radicale list --current --json': exit status 127


  Could not start dynamically linked executable: /tmp/railpack/mise/mise-2025.10.4
  NixOS cannot run dynamically linked executables intended for generic
  linux environments out of the box. For more information, see:
  https://nix.dev/permalink/stub-ld

  ✖ Failed to run mise command '/tmp/railpack/mise/mise-2025.10.4 latest python@3.13': exit status 127


  Could not start dynamically linked executable: /tmp/railpack/mise/mise-2025.10.4
  NixOS cannot run dynamically linked executables intended for generic
  linux environments out of the box. For more information, see:
  https://nix.dev/permalink/stub-ld

[iloveitaly]

@c4lliope railpack doesn't use nix—did you intent to submit this PR to railpack? Let me know what I'm missing!

[coffee-cup]

If we merge this then the release action

[coffee-cup]

The release action should be updated to bump this, otherwise it will always be out of date

[coffee-cup]

railpack doesn't use nix—did you intent to submit this PR to railpack? Let me know what I'm missing!

I think this is so people can install Railpack with Nix.

is there an ENV var we can use to pass in the NixOS-packaged mise path?

@c4lliope there is not, but we can add one. What would you expect it to be?

[c4lliope]

Sorry to drop comms, I'm at https://www.dcstw.com/ and the schedule is packed!

[iloveitaly]

@c4lliope friendly bump here! Would be great to get this merged in.