Mintlayer Connect SDK

A lightweight JavaScript/TypeScript SDK to connect your dApp to the Mintlayer blockchain. It allows you to build and request to sign transactions using a compatible wallet like Mojito.

Features

• 🔐 Secure connection to Mintlayer wallets
• 📦 Transaction builder for all major transaction types
• 🧮 Type-safe interfaces (TypeScript support)
• 🔄 UTXO-based transaction handling
• 🪙 Token minting, burning, and NFT issuance

Installation

npm install @mintlayer/sdk

or with yarn:

yarn add @mintlayer/sdk

Usage

1. Connect to wallet

import { Client } from '@mintlayer/sdk';

const client = new Client();
await client.connect(); // Opens wallet connection prompt

2. Send Transfer

await client.transfer({
  to: 'tmt1qxyz...',            // recipient address
  amount: 10,                   // in human-readable units
  token_id: 'tmltk1...',        // optional, omit for base coin
});

3. Build transaction manually

const tx = await client.buildTransaction({
  type: 'BurnToken',
  params: {
    amount: 10,
    token_id: 'tmltk1...',
    token_details: {
      authority: 'tmt1q...',
      number_of_decimals: 8,
      // ... other metadata
    },
  },
});

4. Sign transaction

Since version 1.0.17 the SDK supports signing transactions using class Signer:

import { Signer } from '@mintlayer/sdk';
 
const private_keys = {
    'tmt1qxyz...': new Uint8Array([0,0,0,...]) // Replace with actual private key bytes
};

const signer = new Signer(private_keys);

const transaction = await client.buildTransaction({
  type: 'Transfer',
  params: {
    to: 'tmt1qxyz...', // recipient address
    amount: 10,        // in human-readable units
  },
});

const signed_transaction = await signer.signTransaction(transaction);

To use helper methods, you have to implement AccountProvider interface that will handle connection and signing requests. By default, SDK communicates to Mojito Account Provider. Here's an example implementation:

class MyAccountProvider implements AccountProvider {
  async connect() {
    return addresses; // Replace with actual addresses
  }

  async restore() {
    return addresses;
  }

  async disconnect() {
    return Promise.resolve()
  }

  async request(method, params) {
    if( method === 'signTransaction') {
      const signer = new Signer(private_keys);
      const transaction_signed = signer.sign(params.txData);

      return Promise.resolve(transaction_signed);
    }
    throw new Error(`Method ${method} not implemented`);
  }
}

const client = await Client.create({
  network: 'testnet',
  autoRestore: false,
  accountProvider: new MyAccountProvider()
});

await client.connect();

const signed_transaction = await client.transfer({
  to: 'tmt1q9mfg7d6ul2nt5yhmm7l7r6wwyqkd822rymr83uc',
  amount: 10,
});

Supported transaction types

• Transfer
• BurnToken
• IssueFungibleToken
• IssueNft
• MintToken
• UnmintToken
• LockTokenSupply
• ChangeMetadataUri
• ChangeTokenAuthority
• FreezeToken
• UnfreezeToken
• DataDeposit
• CreateDelegationId
• DelegationStake
• DelegationWithdraw
• CreateOrder
• ConcludeOrder
• FillOrder

Development & Testing

• Clone the repo and run npm install
• More tests coming soon (Jest + mocks)
• Contributions welcome!

Security

All sensitive actions (signing, wallet access) require user approval via the wallet. Private keys are never exposed.

License

MIT

Need help?

Join the community or open an issue on GitHub.