{ ... }:
{
  perSystem =
    { pkgs, ... }:
    {
      packages.gh-act =
        (pkgs.writeShellApplication {
          name = "gh-act";
          runtimeInputs = with pkgs; [
            yq
            coreutils
          ];
          text = ''
            workflow="''${1:-.github/workflows/ci.yml}"

            if [ ! -f "$workflow" ]; then
              echo "Usage: gh-act [workflow.yml]"
              echo "Run GitHub Actions workflow steps locally"
              exit 1
            fi

            echo "Running: $workflow"
            echo "=================="

            # Extract each step and run it
            for job in $(yq -r '.jobs | keys[]' "$workflow"); do
              echo "=== Job: $job ==="
              step_count=$(yq -r ".jobs[\"$job\"].steps | length" "$workflow")
              for i in $(seq 0 $((step_count - 1))); do
                name=$(yq -r ".jobs[\"$job\"].steps[$i].name // \"Step $i\"" "$workflow")
                run_cmd=$(yq -r ".jobs[\"$job\"].steps[$i].run // empty" "$workflow")
                
                if [ -n "$run_cmd" ]; then
                  echo ">>> Running: $name"
                  echo "---"
                  bash -c "$run_cmd"
                  echo
                fi
              done
            done
          '';
        }).overrideAttrs
          { passthru.usage = builtins.readFile ./usage.kdl; };
    };
}