Integration Patterns

Depending on your protocol's architecture, there are several ways to implement Herald.

1. Backend Trigger (Recommended)

This is the most common pattern. Your backend service monitors on-chain events or user actions and calls the Herald SDK to send notifications.

• Pros: Secure API keys, easy rate limiting, handles retries gracefully.
• Cons: Requires backend infrastructure.

2. Serverless / Edge Functions

Perfect for light-weight protocols. Use Next.js API routes or Vercel Functions to trigger notifications.

• Pros: Zero maintenance, scales automatically.
• Cons: Cold starts might slightly delay delivery.

3. Webhook Bridge

If you use off-chain infrastructure like Telegram bots, you can send notifications directly to Herald from your existing alert system.

• Pros: Minimal code changes.
• Cons: Less granular control over user preferences.

4. On-Chain Event Listener

Herald can be configured to listen for specific Solana program events and automatically notify users when they occur.

• Pros: Truly decentralized notifications.
• Cons: Higher latency and configuration complexity.

Example: Liquidator Alert

// Your liquidation bot
if (healthFactor < 1.0) {
  await herald.notify({
    wallet: targetUser,
    subject: "Liquidation Incoming",
    body: "Health factor critical.",
    category: "defi"
  });
}