anchor.diff:          uid="$(id -u)"
           gid="$(id -g)"
           pwd="$(pwd)"
  -        starttime="$(date +%s)"
  +        starttime="$(now)"
  +
  +        function log() {
  +          printf "%05d %s\n" $(($(now) - $starttime)) "$1"
  +        }
  +
  +        function err() {
  +          log "error: $1"
  +        }
   
           function run_one_build() {
             export build="$(readlink -m "$(mktemp -dp "$pwd")")"
  
positive.code:           chmod a+x .
            chmod a+w -R $build
  
            echo "[Starting libvirt machines]"
            ${pkgs.libvirt}/bin/virsh -c "${cfg.connectionURI}" \
              "${virshCreateCmds}" >/dev/null
            ${pkgs.libvirt}/bin/virsh -c "${cfg.connectionURI}" \
  
negative.code:       timeouts = {
          sleepBetweenRetries = mkOption {
            type = types.int;
            default = 15;
          };
          singleTryTimeout = mkOption {
            type = types.int;
  