TxForge

TxForge is an industrial strength transaction builder. Re-built on top of nimble, TxForge 2.0 is an ultra-lightweight, ultra-flexible, essential part of any respectable Bitcoin builders' toolkit.

• simple, human-friendly declarative API for composing transactions
• extendable and flexible - can forge transactions with any script template imaginable
• under the hood it's powered by nimble, less that 1/5 the size of moneybutton/bsv v2 and up to 4 times as fast!
• a robust library using well-tested, modern javascript

The legacy version of TxForge, powered by bsv v2, can be found on the legacy branch.

Sponsors

Supported by:

Your sponsorship will help us continue to release and maintain software that Bitcoin businesses and developers depend on.

👉 Sponsor Chronos Labs' open source work

Upgrading

If you've used previous versions of TxForge, conceptually everything is the same. However, v2.0 is a rewrite from top to bottom, powered by a new Bitcoin library, and incorporates some API changes, most notably with how Casts are defined and used.

Full more details, check out the TxForge 2 upgrade notes.

Quick start

Install TxForge with npm or yarn:

npm install txforge
# or
yarn add txforge

Alternatively use in a browser via CDN:

<script src="https://unpkg.com/@runonbitcoin/nimble"></script>
<script src="https://unpkg.com/txforge/dist/txforge.min.js"></script>

<!-- or use the bundled version which includes nimble -->
<script src="https://unpkg.com/txforge/dist/txforge.bundled.min.js"></script>

Grab your tools and put on your safety googles. Lets forge a transaction... it's hammer time!

import { forgeTx, toUTXO, casts } from 'txforge'

// We'll use these Casts in our transaction
const { P2PKH, OpReturn } = casts

// You'll need UTXOs to fund a transaction. Use the `toUTXO` helper to turn
// your UTXO data into the required objects.
const utxo = toUTXO({
  txid,       // utxo transaction id
  vout,       // utxo output index
  satoshis,   // utxo amount
  script      // utxo lock script
})

// Forge a transaction
const tx = forgeTx({
  inputs: [
    P2PKH.unlock(utxo, { privkey: myPrivateKey })
  ],
  outputs: [
    P2PKH.lock(5000, { address: '1DBz6V6CmvjZTvfjvWpvvwuM1X7GkRmWEq' }),
    OpReturn.lock(0, { data: ['meta', '1DBz6V6CmvjZTvfjvWpvvwuM1X7GkRmWEq', txid] })
  ],
  change: { address: '1Nro9WkpaKm9axmcfPVp79dAJU1Gx7VmMZ' }
})

// And behold! Forged by the Gods and found by a King - a transaction is born.
console.log(tx.toHex())

And that's it. Really. One function that returns a fully built and signed transaction, ready to send off to your favourite transaction processor.

But there's more, much more. When you're ready, grab a coffee and dive into the following to discover how TxForge can be used to lock and unlock any combination of script template you can imagine.

• Understanding Casts
• Creating custom Casts
• Building Scripts with TxForge

License

TxForge is open source and released under the Apache-2 License.

Copyright (c) 2020-2022 Chronos Labs Ltd.