[ 'domain' => env('MAILGUN_DOMAIN'), 'secret' => env('MAILGUN_SECRET'), 'endpoint' => env('MAILGUN_ENDPOINT', 'api.mailgun.net'), ], 'postmark' => [ 'token' => env('POSTMARK_TOKEN'), ], 'ses' => [ 'key' => env('SES_KEY'), 'secret' => env('SES_SECRET'), 'region' => 'us-east-1', ], ];