Vonage (Nexmo)

Vonage (previously Nexmo) is a direct Twilio competitor. Similar coverage, similar pricing. Some regions are cheaper on Vonage, others on Twilio — worth comparing if you're at scale.

Pricing

• Trial — free credits.
• Per-message — similar band to Twilio, starts at a few cents per SMS. Country matrix: https://developer.vonage.com/en/messaging/sms/overview.

Setup

1. Create an account at https://vonage.com.
2. Copy API key and API secret from the dashboard.
3. Optionally buy a sender number; some countries also allow alphanumeric senders.

import "github.com/gopackx/go-notification/channel/sms/vonage"

notifier.RegisterChannel("sms", vonage.New(vonage.Config{
    APIKey:    os.Getenv("VONAGE_API_KEY"),
    APISecret: os.Getenv("VONAGE_API_SECRET"),
    From:      "YourBrand", // or +E.164 number, country-dependent
}))

Configuration reference

Fallback pattern

A common high-reliability setup: Twilio as primary, Vonage as backup.

notifier.RegisterChannel("sms",         twilio.New(/* ... */))
notifier.RegisterChannel("sms-backup",  vonage.New(/* ... */))

func (n OTP) Via(u notification.Notifiable) []string {
    return []string{"sms"}
}

// In your OnError handler, trigger a retry via "sms-backup"

Troubleshooting

• delivery-status: Undeliverable — country/carrier block. Try a different sender type (short code vs alphanumeric).
• Alphanumeric sender rejected — US and Canada don't allow alphanumeric senders. Use a proper long code or toll-free.
• Billing surprise — some countries (Russia, parts of the Middle East) are 10× typical per-message cost. Check the rate sheet before rolling out.