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Server-only
This page covers your server webhook handler. The client triggers delegation; your server verifies, decrypts, and stores materials.
When a delegation is triggered, your endpoint receives a webhook named wallet.delegation.created. The delegated materials are in data. 
{
  "messageId": "f44da9f0-a5b5-47f6-965f-f04af51c903e",
  "eventId": "2cf779a8-89da-486f-974e-2b77b738e4ac",
  "eventName": "wallet.delegation.created",
  "timestamp": "2025-10-01T15:13:26.348Z",
  "webhookId": "9a31fefc-64e4-4551-81da-1502eacc852d",
  "userId": "7eb7843b-2a4d-4f69-b95e-d219f0662fda",
  "environmentId": "53728749-1f19-4cab-becf-b88f952c3a3c",
  "environmentName": "sandbox",
  "data": {
    "chain": "EVM",
    "encryptedDelegatedShare": {
      "alg": "HYBRID-RSA-AES-256",
      "iv": "dzePdAUMQd6lWQngEXWPdQ",
      "ct": "pJIT5UU...XcWeYsXhygL2QbQcWZK6Rs5_CuiCDb_dHC_7P1tC...",
      "tag": "Yq8bpMU8huIx7UzUUUgI9Q",
      "ek": "uix2E6E...Keru7HWqeu7ktw"
    },
    "encryptedWalletApiKey": {
      "alg": "HYBRID-RSA-AES-256",
      "ct": "PzeliI...0kB9C0",
      "ek": "iWJgZQ...rxt",
      "iv": "RpC5nw1b4udgJqnC1p0evQ",
      "kid": "dynamic_rsa_lSuvWlCy",
      "tag": "-ZtmOG6gYTzS53wVMNK0Ig"
    },
    "publicKey": "0xd74ff800a3c6f66ecd217118aaa6fb1c916fa4e2",
    "userId": "7eb7843b-2a4d-4f69-b95e-d219f0662fda",
    "walletId": "25193936-3ecd-4c1b-84e6-9eabc82e53c2"
  }
}

​
Verify → Decrypt → Store

  1. Verify the webhook signature. Use your webhook secret and the x-dynamic-signature-256 header: compute HMAC-SHA256 of the raw request body with the secret and compare to the header value in constant time. Only proceed if the signature is valid.
import * as crypto from "crypto";

export const verifySignature = ({
  secret,
  signature,
  payload,
}: { secret: string; signature: string; payload: any }) => {
  const payloadSignature = crypto
    .createHmac("sha256", secret)
    .update(JSON.stringify(payload))
    .digest("hex");
  const trusted = Buffer.from(`sha256=${payloadSignature}`, "ascii");
  const untrusted = Buffer.from(signature, "ascii");
  return crypto.timingSafeEqual(trusted, untrusted);
};
The payload you pass to verifySignature must match exactly how it was sent (same JSON structure); otherwise verification will fail.
  1. Decrypt data.encryptedDelegatedShare and data.encryptedWalletApiKey.
  2. Store userId, walletId, and decrypted materials securely (e.g., envelope encryption, KMS, at-rest encryption).
Encryption fields
alg: hybrid (RSA‑OAEP + AES‑256‑GCM); iv: AES IV; ct: ciphertext; tag: GCM tag; ek: encrypted content‑encryption key; kid: key identifier for rotation.

​
Example: Node (using Dynamic SDK)

We provide a helper function to handle decryption for you. Install the SDK: 
npm install @dynamic-labs-wallet/node
Then use the decryptDelegatedWebhookData function: 
import { decryptDelegatedWebhookData } from '@dynamic-labs-wallet/node';

// In your webhook handler, after verifying the signature
const webhookData = req.body; // The webhook payload

const { decryptedDelegatedShare, decryptedWalletApiKey } =
  decryptDelegatedWebhookData({
    privateKeyPem: process.env.YOUR_PRIVATE_KEY, // Your RSA private key
    encryptedDelegatedKeyShare: webhookData.data.encryptedDelegatedShare,
    encryptedWalletApiKey: webhookData.data.encryptedWalletApiKey,
  });

// Now securely store these decrypted materials
// decryptedDelegatedShare: ServerKeyShare object
// decryptedWalletApiKey: string
If a delivery fails, you can replay it from the dashboard. Use the eventId as an idempotency key.

Storage Best Practices

Learn how to securely store decrypted delegated materials.

Developer Actions

Learn how to use the delegated materials.