IOTA support on Turnkey

Address derivation

Turnkey fully supports IOTA addresses derived from the Ed25519 curve.

Transaction construction and signing

Turnkey supports IOTA transaction signing through the core signing capabilities. We provide an example repository that demonstrates how to construct and sign IOTA transactions:

• examples/chain-integrations/with-iota: demonstrates transaction construction and broadcast on IOTA.

Example

Here’s a practical example showing how to integrate Turnkey with the IOTA SDK:

import * as dotenv from 'dotenv';
import * as path from 'path';
import { IotaClient, getFullnodeUrl } from '@iota/iota-sdk/client';
import { Transaction } from '@iota/iota-sdk/transactions';
import { Ed25519PublicKey } from '@iota/iota-sdk/keypairs/ed25519';
import { messageWithIntent } from '@iota/iota-sdk/cryptography';
import { Turnkey } from '@turnkey/sdk-server';
import { blake2b } from '@noble/hashes/blake2b';
import { bytesToHex } from '@noble/hashes/utils';

dotenv.config({ path: path.resolve(process.cwd(), '.env.local') });
function toSerializedSignature({
  signature,
  pubKey,
}: {
  signature: Uint8Array;
  pubKey: Ed25519PublicKey;
}): string {
  const scheme = new Uint8Array([0x00]); // ED25519 flag
  const pubKeyBytes = pubKey.toRawBytes();
  const serialized = new Uint8Array(
    scheme.length + signature.length + pubKeyBytes.length
  );
  serialized.set(scheme, 0);
  serialized.set(signature, scheme.length);
  serialized.set(pubKeyBytes, scheme.length + signature.length);
  return Buffer.from(serialized).toString('base64');
}

async function main() {
  // load the variables from .env
  // IOTA_ADDRESS and IOTA_PUBLIC_KEY of the Turnkey signer
  const {
    ORGANIZATION_ID,
    API_PRIVATE_KEY,
    API_PUBLIC_KEY,
    IOTA_ADDRESS,
    IOTA_PUBLIC_KEY,
  } = process.env;

  if (IOTA_ADDRESS === undefined || IOTA_PUBLIC_KEY === undefined) {
    throw new Error('IOTA_ADDRESS or IOTA_PUBLIC_KEY not set in .env.local');
  }

  // sending to the same address
  const recipient = IOTA_ADDRESS;
  const amount = 1_000_000n; // 0.001 IOTA

  const turnkeyClient = new Turnkey({
    apiBaseUrl: 'https://api.turnkey.com',
    apiPrivateKey: API_PRIVATE_KEY!,
    apiPublicKey: API_PUBLIC_KEY!,
    defaultOrganizationId: ORGANIZATION_ID!,
  });

  const provider = new IotaClient({ url: getFullnodeUrl('testnet') });
  const publicKey = new Ed25519PublicKey(Buffer.from(IOTA_PUBLIC_KEY!, 'hex'));

  // if (publicKey.toIotaAddress() !== IOTA_ADDRESS) {
  //   throw new Error('IOTA_PUBLIC_KEY does not match IOTA_ADDRESS');
  // }

  // fetch the user's IOTA coin objects
  const coins = await provider.getCoins({
    owner: IOTA_ADDRESS!,
    coinType: '0x2::iota::IOTA',
  });
  if (!coins.data.length) throw new Error('No IOTA coins');

  const tx = new Transaction();
  tx.setSender(IOTA_ADDRESS!);
  tx.setGasPrice(await provider.getReferenceGasPrice());
  tx.setGasBudget(5_000_000n);
  tx.setGasPayment([
    {
      objectId: coins.data[0]!.coinObjectId,
      version: coins.data[0]!.version,
      digest: coins.data[0]!.digest,
    },
  ]);
  const coin = tx.splitCoins(tx.gas, [tx.pure('u64', amount)]);
  tx.transferObjects([coin], tx.pure.address(recipient));

  const txBytes = await tx.build();

  const intentMsg = messageWithIntent('TransactionData', txBytes);
  const digest = blake2b(intentMsg, { dkLen: 32 });

  const { r, s } = await turnkeyClient.apiClient().signRawPayload({
    signWith: IOTA_ADDRESS!,
    payload: bytesToHex(digest),
    encoding: 'PAYLOAD_ENCODING_HEXADECIMAL',
    hashFunction: 'HASH_FUNCTION_NOT_APPLICABLE',
  });

  const signature = Buffer.from(r + s, 'hex');
  const serialized = toSerializedSignature({ signature, pubKey: publicKey });

  const result = await provider.executeTransactionBlock({
    transactionBlock: Buffer.from(txBytes).toString('base64'),
    signature: serialized,
    requestType: 'WaitForEffectsCert',
    options: { showEffects: true },
  });

  console.log('Transaction digest:', result.digest);
}

main().catch((err) => {
  console.error('Error:', err);
  process.exit(1);
});

IOTA network support

Turnkey supports:

• IOTA Mainnet
• IOTA Testnet
• IOTA Devnet

Key features for IOTA

• Ed25519 Signing: Turnkey fully supports the Ed25519 curve used by IOTA
• Raw Transaction Signing: Sign any IOTA transaction format with Turnkey’s flexible signing API
• Integration Example: Our example repository provides a reference implementation

Benefits of using Turnkey with IOTA

• Secure Key Management: Private keys never leave Turnkey’s secure infrastructure
• Developer Friendly: Integrate with existing IOTA development workflows
• Signing Policies: Apply custom policies to control transaction approvals
• Multi-user Support: Manage multiple IOTA addresses under a single organization

If you’re building on IOTA and need assistance with Turnkey integration, feel free to contact us at [e-mail], on X, or on Slack.