Paddle Webhooks Skill

When to Use This Skill

• Setting up Paddle webhook handlers
• Debugging signature verification failures
• Understanding Paddle event types and payloads
• Handling subscription, transaction, or customer events

Verification (core)

Paddle signs every webhook with HMAC-SHA256 over timestamp:rawBody. The Paddle-Signature header is ts=<unix>;h1=<hex> (multiple h1= values appear during secret rotation). Pass the raw request body — don't JSON.parse first.

The official @paddle/paddle-node-sdk exposes paddle.webhooks.unmarshal(rawBody, secretKey, signature) which verifies and parses in one call. For Python (or when not using the SDK), verify manually:

Node:

const crypto = require('crypto');

function verifyPaddleSignature(rawBody, signatureHeader, secret) {
  const parts = signatureHeader.split(';');
  const ts = parts.find(p => p.startsWith('ts='))?.slice(3);
  const signatures = parts.filter(p => p.startsWith('h1=')).map(p => p.slice(3));
  if (!ts || signatures.length === 0) return false;

  const expected = crypto
    .createHmac('sha256', secret)
    .update(`${ts}:${rawBody}`)
    .digest('hex');

  return signatures.some(sig =>
    crypto.timingSafeEqual(Buffer.from(sig), Buffer.from(expected))
  );
}

Python:

import hmac, hashlib

def verify_paddle_signature(raw_body: str, signature_header: str, secret: str) -> bool:
    parts = signature_header.split(';')
    ts = next((p[3:] for p in parts if p.startswith('ts=')), None)
    signatures = [p[3:] for p in parts if p.startswith('h1=')]
    if not ts or not signatures:
        return False

    expected = hmac.new(
        secret.encode(), f"{ts}:{raw_body}".encode(), hashlib.sha256
    ).hexdigest()

    return any(hmac.compare_digest(sig, expected) for sig in signatures)

For complete handlers with route wiring, event dispatch, and tests, see:

• examples/express/ - Full Express implementation
• examples/nextjs/ - Next.js App Router implementation
• examples/fastapi/ - Python FastAPI implementation

Common Event Types

For full event reference, see Paddle Webhook Events

Environment Variables

PADDLE_WEBHOOK_SECRET=pdl_ntfset_xxxxx_xxxxx   # From notification destination settings

Local Development

# Start tunnel (no account needed)
npx hookdeck-cli listen 3000 paddle --path /webhooks/paddle

Reference Materials

• references/overview.md - Paddle webhook concepts
• references/setup.md - Dashboard configuration
• references/verification.md - Signature verification details