{
  # Uses a local `path:` input to consume pure data from another flake.
  description = "A minimal local path input example";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    catalog.url = "path:./catalog";
  };

  outputs =
    {
      self,
      nixpkgs,
      catalog,
      ...
    }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; };

      inherit (catalog.lib)
        releaseName
        serviceOwners
        rolloutWaves
        ;

      renderWave =
        wave:
        "${wave.name}: ${builtins.concatStringsSep ", " wave.services} with approvals ${builtins.concatStringsSep ", " wave.approvals}";

      ownerLines = pkgs.lib.mapAttrsToList (service: owner: "${service}: ${owner}") serviceOwners;

      planText = builtins.concatStringsSep "\n" (
        [
          "release: ${releaseName}"
          "owners:"
        ]
        ++ ownerLines
        ++ [
          "waves:"
        ]
        ++ map renderWave rolloutWaves
      );
    in
    {
      packages.${system}.default = pkgs.writeShellApplication {
        name = "show-local-plan";
        text = ''
          cat <<'EOF'
          ${planText}
          EOF
        '';
      };

      checks.${system}.catalog-is-used = pkgs.runCommand "local-path-input-check" { } ''
        plan="$(${pkgs.lib.getExe self.packages.${system}.default})"

        printf '%s\n' "$plan" | grep -q '^release: checkout-2026-05$'
        printf '%s\n' "$plan" | grep -q '^billing: team-revenue$'
        printf '%s\n' "$plan" | grep -q '^production: api, billing, worker with approvals change-advisory, finance-signoff$'

        echo ok > "$out"
      '';
    };
}