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After deploying your contract and adding it to the dashboard, update your offchain integration to target your contract address and pass attestations onchain.
1

Update API requests

Replace verification_hash with to (your contract address).
2

Pass attestations to your contract

Include the attestation struct when calling predicated functions.

​
Backend Changes

Replace verification_hash with your contract address in the to field.
app.post('/api/predicate/attestation', async (req, res) => {
  const { userAddress, contractAddress } = req.body;

  const response = await fetch('https://api.predicate.io/v2/attestation', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'x-api-key': process.env.PREDICATE_API_KEY,
    },
    body: JSON.stringify({
      to: contractAddress,
      from: userAddress,
      chain: 'base',
    }),
  });

  const result = await response.json();

  if (!result.is_compliant) {
    return res.status(403).json({ error: 'Not compliant' });
  }

  res.json({ attestation: result.attestation });
});

​
Request Parameters

FieldDescription
toYour deployed contract address
fromThe user’s wallet address
chainChain name (e.g., base, ethereum, arbitrum)

​
Frontend Changes

Fetch the attestation and pass it to your contract function.
// 1) Fetch attestation from your backend
const { attestation } = await fetch('/api/predicate/attestation', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    userAddress: account,
    contractAddress: VAULT_ADDRESS,
  }),
}).then(r => r.json());

// 2) Call your contract with the attestation
const tx = await vault.deposit(
  {
    uuid: attestation.uuid,
    expiration: attestation.expiration,
    attester: attestation.attester,
    signature: attestation.signature,
  },
  { value: depositAmount }
);

​
Attestation Struct

FieldTypeDescription
uuidbytes16Unique identifier for replay protection
expirationuint256Unix timestamp when the attestation expires
attesteraddressAddress of the Predicate attester that signed
signaturebytesECDSA signature over the attestation