{ nixpkgs, declInput }: let pkgs = import nixpkgs {}; in {
  # this file generates the spec.json file which contains all the jobsets (list of jobs)
  # a job set may be all the hosts of a user of stockholm

  # what we need to get here is for each host we want to build the "input"
  # from its source.nix and add them to the "inputs" field
  # in addition to that we need to define how a system is built inside the
  # "local" release.nix

  # nixexprinput points to the path expression which should be used for evaluation
  # nixexprpath is the file which will be built.
  # that means in best case we should be able to use default.nix from
  # <stockholm> after nixos-config is set!

  jobsets = pkgs.runCommand "spec.json" {} ''
    cat <<EOF
    ${builtins.toXML declInput}
    EOF
    cat > $out <<EOF
    {
        "makefu x.r": {
            "enabled": 1,
            "hidden": false,
            "description": "host build",
            "nixexprinput": "src",
            "nixexprpath": "host.nix",
            "checkinterval": 15,
            "schedulingshares": 100,
            "enableemail": false,
            "emailoverride": "",
            "keepnr": 3,
            "inputs": {
                "src": { "type": "git", "value": "http://cgit.euer.krebsco.de/hydra-stockholm", "emailresponsible": false },
                "stockholm": { "type": "git", "value": "http://cgit.krebsco.de/stockholm", "emailresponsible": false },
                "nixpkgs": { "type": "git", "value": "https://github.com/makefu/nixpkgs 51810e0", "emailresponsible": false },
                "nixos-hardware": { "type": "git", "value": "https://github.com/nixos/nixos-hardware.git 8a05dc9", "emailresponsible": false },
                "python": { "type": "git", "value": "https://github.com/garbas/nixpkgs-python cac319b7", "emailresponsible": false },
                "nixos-config": { "type": "path", "value": "/var/src/stockholm/makefu/1systems/x/config.nix", "emailresponsible": false },
                "secrets": { "type": "path", "value": "/var/src/stockholm/makefu/6tests/data/secrets", "emailresponsible": false },
                "host": { "type": "string", "value": "x", "emailresponsible": false },
                "owner": { "type": "string", "value": "makefu", "emailresponsible": false }
            }
        }
    }
    EOF
  '';
}