print STDERR "evaluator ${evaluator}\n";

    (my $res, my $jobsJSON, my $stderr) = captureStdoutStderr(10800,
        $evaluator, $nixExprFullPath, "--gc-roots-dir", getGCRootsDir, "-j", 1, inputsToArgs($inputInfo, $exprType));

    my @cmd = ($evaluator, $nixExprFullPath, "--gc-roots-dir", getGCRootsDir, "-j", 1, inputsToArgs($inputInfo, $exprType));
    if (defined $ENV{'HYDRA_DEBUG'}) {
        sub escape {
            my $s = $_;
            $s =~ s/'/'\\''/g;
            return "'" . $s . "'";
        }
        my @escaped = map escape, @cmd;
        print STDERR "evaluator: @escaped\n";
    }
    (my $res, my $jobsJSON, my $stderr) = captureStdoutStderr(10800, @cmd);

my $dryRun = defined $ENV{'HYDRA_DRY_RUN'};

            $jobset->update({ lastcheckedtime => time, fetcherrormsg => $msg });

            $jobset->update({ lastcheckedtime => time, fetcherrormsg => $msg }) if !$dryRun;

    if (defined $prevEval && $prevEval->hash eq $argsHash) {

    if (defined $prevEval && $prevEval->hash eq $argsHash && !$dryRun) {

    if ($dryRun) {
        foreach my $name (keys %{$jobs}) {
            my $job = $jobs->{$name};
            if (defined $job->{drvPath}) {
                print STDERR "good job $name: $job->{drvPath}\n";
            } else {
                print STDERR "failed job $name: $job->{error}\n";
            }
        }
        return;
    }

        });

        }) if !$dryRun;

        });

        }) if !$dryRun;