// bootstrap/app.php
$app->configureMonologUsing(function ($monolog) {
    /** @var MonologLogger $monolog */
    $monolog->pushHandler(new MonologHandlerStreamHandler('php://stdout', MonologLogger::DEBUG));
});

protected function schedule(Schedule $schedule)
{
    Log::info('Running cronjobs.');

    $schedule
        ->command('update:daily')
        ->timezone('America/Los_Angeles')
        ->everyMinute();
}

Jan 19 09:42:15 service app/scheduler.4140: [2018-01-19 17:42:14] lumen.INFO: Running cronjobs. [] []
Jan 19 09:42:15 service app/scheduler.4140: Running scheduled command: '/app/.heroku/php/bin/php' artisan update:daily > '/dev/null' 2>&1

web: vendor/bin/heroku-php-nginx -C heroku-nginx.conf -l storage/logs/cronjobs.log public/