Salt SDK

TypeScript client for Salt, an open MPC self-custodial infrastructure for organisations. With Salt, anyone can spin up a system of self-sovereignty for self-custodial wealth management, including delegations to 3rd parties such as asset managers, robo-advisors or agents.

⚠️ Pre-release software. Before upgrading:

• Accounts created with this version are incompatible with previous versions.
• Testnet accounts will be wiped in an upcoming release - do not treat them as long-term.
• Mainnet is not yet supported — this version creates testnet accounts only.

Documentation

📃 API Reference

Install

npm install salt-sdk viem
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viem is a peer dependency.

Example

import { Salt } from 'salt-sdk';
import {
  createPublicClient,
  createWalletClient,
  http,
  parseEther,
  type Hex,
} from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import { arbitrumSepolia, sepolia } from 'viem/chains';

// Create an instance — TESTNET uses Arbitrum Sepolia for orchestration
const salt = new Salt({ environment: 'TESTNET' });

// Set up a viem wallet client (orchestration chain must match the environment)
const account = privateKeyToAccount(process.env.PRIVATE_KEY as Hex);
const walletClient = createWalletClient({
  account,
  chain: arbitrumSepolia,
  transport: http(),
});

// Authenticate with SIWE
await salt.authenticate(walletClient);

// Fetch your organisations and accounts
const orgs = await salt.getOrganisations();
const accounts = await salt.getAccounts(orgs[0].id);

// Submit a native ETH transfer to Sepolia
const publicClient = createPublicClient({
  chain: sepolia,
  transport: http(process.env.SEPOLIA_RPC_URL),
});

const ceremony = await salt.submitTx({
  accountId: accounts[0].id,
  to: '0x000000000000000000000000000000000000dEaD',
  value: parseEther('0.01'),
  chainId: 11155111,
  userAddress: account.address,
  walletClient,
  publicClient,
});

// Track progress: proposing → signing → broadcasting → confirming → success | failure
ceremony.on('stateChanged', ({ stage }) => console.log('tx is now', stage));

// Wait for MPC signing + broadcast to complete
const { transaction } = await ceremony.wait();
console.log('tx hash:', transaction.txHash);
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See More: Salt constructor · authenticate · getOrganisations · getAccounts · submitTx

Two-network model

Every Salt transaction involves two networks:

• Orchestration network — where MPC signing coordination happens. Set by the environment:
  • STAGING & TESTNET = Arbitrum Sepolia
  • MAINNET = Arbitrum One
• Destination network — where the transaction actually executes. Set by chainId + publicClient in submitTx. Can be any supported EVM chain.

Tracking progress

const ceremony = await salt.submitTx({
  /* ... */
});

ceremony.on('stateChanged', ({ stage }) => {
  console.log('transaction is now', stage);
  // proposing → signing → broadcasting → confirming → success | failure
});

const { transaction } = await ceremony.wait();
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See More: submitTx · TransactionHostCeremony

Policies

Policies control which transactions robo guardians will co-sign. Create them per account and chain. If a transaction violates a policy, the robos refuse to sign and it fails before broadcast.

// Restrict ERC-20 approve() calls: only allow a specific spender, cap the amount
await salt.createAccountPolicy({
  accountId: accounts[0].id,
  organisationId: orgs[0].id,
  type: 'contract_param_restriction',
  chain: '11155111', // Sepolia
  params: {
    restrictions: [
      {
        contractAddress: '0x1c7D4B196Cb0C7B01d743Fbc6116a902379C7238', // USDC on Sepolia
        functionSignature: 'approve(address,uint256)',
        paramIndex: 0, // spender argument
        operator: 'eq',
        value: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045',
      },
      {
        contractAddress: '0x1c7D4B196Cb0C7B01d743Fbc6116a902379C7238',
        functionSignature: 'approve(address,uint256)',
        paramIndex: 1, // amount argument
        operator: 'lte',
        value: '1000000', // 1 USDC (6 decimals)
      },
    ],
  },
});
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See More: createAccountPolicy · ContractParamRestriction · PolicyParams

Contract calls

Pass encoded calldata via data. The transaction below is valid against the contract_param_restriction policy above — the spender matches and the amount is within the cap.

import { encodeFunctionData, parseAbi } from 'viem';

const data = encodeFunctionData({
  abi: parseAbi(['function approve(address spender, uint256 amount)']),
  functionName: 'approve',
  args: [
    '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045', // allowed spender
    500_000n, // 0.5 USDC — within the 1 USDC cap
  ],
});

const ceremony = await salt.submitTx({
  accountId: accounts[0].id,
  to: '0x1c7D4B196Cb0C7B01d743Fbc6116a902379C7238', // USDC on Sepolia
  value: 0n,
  chainId: 11155111,
  data,
  userAddress: account.address,
  walletClient,
  publicClient,
});

await ceremony.wait();
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See More: submitTx · SendTransactionParams

Organisations and accounts

Organisations group collaborators and own accounts. Accounts are MPC wallets: humans create them via a key-generation ceremony and become signers. Fetch what the authenticated user belongs to with getOrganisations and getAccounts, create new ones with createOrganisation and createAccount, and manage collaborators with inviteCollaborator.

See examples: createOrganisation · inviteCollaborator · updateCollaborator · createAccount · getOrganisations · getAccounts

Robos

Robos belong to an organisation, and are automated co-signers for accounts. Manage robo hosts with createRoboHost and getRoboHost.

See examples: Salt constructor · createRoboHost · getRoboHost · RoboHost

Full API reference and more examples at kagamidigital.github.io/salt-sdk-mirror.