sub logdir {
    my $appdir = setting('appdir');
    my $logroot = $appdir || File::Spec->tmpdir();
    return path($logroot, 'logs');
}

However, our production environments all mount off read-only filesystems, so having logging dependant on appdir won't work. I can write a new logger module that does something like:

sub logdir {
    my $appdir = setting('appdir');
    my $altpath = setting('log_path');
    my $logroot = $appdir || File::Spec->tmpdir();
    return ( $altpath ? $altpath : path($logroot, 'logs') );
}