bitcoinjs-lib/README.md

# BitcoinJS (bitcoinjs-lib)
[![Build Status](https://travis-ci.org/bitcoinjs/bitcoinjs-lib.png?branch=master)](https://travis-ci.org/bitcoinjs/bitcoinjs-lib)
[![NPM](https://img.shields.io/npm/v/bitcoinjs-lib.svg)](https://www.npmjs.org/package/bitcoinjs-lib)

[![js-standard-style](https://cdn.rawgit.com/feross/standard/master/badge.svg)](https://github.com/feross/standard)

A javascript Bitcoin library for node.js and browsers.

Released under the terms of the [MIT LICENSE](LICENSE).

## Should I use this in production?
If you are thinking of using the *master* branch of this library in production, **stop**.
Master is not stable; it is our development branch, and [only tagged releases may be classified as stable](https://github.com/bitcoinjs/bitcoinjs-lib/tags).


## Can I trust this code?
> Don't trust. Verify.

We recommend every user of this library and the [bitcoinjs](https://github.com/bitcoinjs) ecosystem audit and verify any underlying code for its validity and suitability,  including reviewing any and all of your project's dependencies.

Mistakes and bugs happen, but with your help in resolving and reporting [issues](https://github.com/bitcoinjs/bitcoinjs-lib/issues), together we can produce open source software that is:

- Easy to audit and verify,
- Tested, with test coverage >95%,
- Advanced and feature rich,
- Standardized, using [standard](http://github.com/standard/standard) and Node `Buffer`'s throughout, and
- Friendly, with a strong and helpful community, ready to answer questions.

## Documentation
Presently,  we do not have any formal documentation other than our [examples](#examples), please [ask for help](https://github.com/bitcoinjs/bitcoinjs-lib/issues/new) if our examples aren't enough to guide you.


## Installation
``` bash
npm install bitcoinjs-lib
```

Typically we support the [Node Maintenance LTS version](https://github.com/nodejs/Release).
If in doubt, see the [.travis.yml](.travis.yml) for what versions are used by our continuous integration tests.

**WARNING**: We presently don't provide any tooling to verify that the release on `npm` matches GitHub.  As such, you should verify anything downloaded by `npm` against your own verified copy.


## Usage

### Browser
The recommended method of using `bitcoinjs-lib` in your browser is through [Browserify](https://github.com/substack/node-browserify).
If you're familiar with how to use browserify, ignore this and carry on, otherwise, it is recommended to read the tutorial at http://browserify.org/.

**NOTE**: We use Node Maintenance LTS features, if you need strict ES5, use [`--transform babelify`](https://github.com/babel/babelify) in conjunction with your `browserify` step (using an [`es2015`](http://babeljs.io/docs/plugins/preset-es2015/) preset).

**NOTE**: If you expect this library to run on an iOS 10 device, ensure that you are using [buffer@5.0.5](https://github.com/feross/buffer/pull/155) or greater.

### Typescript or VSCode users
Type declarations for Typescript [are available](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/0897921174860ec3d5318992d2323b3ae8100a68/types/bitcoinjs-lib) for version `^3.0.0` of the library.

``` bash
npm install @types/bitcoinjs-lib
```

For VSCode (and other editors), it is advised to install the type declarations, as Intellisense uses that information to help you code (autocompletion, static analysis).

**WARNING**: These Typescript definitions are not maintained by the maintainers of this repository, and are instead maintained at [DefinitelyTyped](https://github.com/DefinitelyTyped/DefinitelyTyped).
Please report any issues or problems there.


### Flow
[Flow-type](https://flowtype.org/) definitions for are available in the [flow-*typed* repository](https://github.com/flowtype/flow-typed/tree/master/definitions/npm/bitcoinjs-lib_v2.x.x) for version `^2.0.0` of the library.

You can [download them directly](https://github.com/flowtype/flow-typed/blob/master/definitions/npm/bitcoinjs-lib_v2.x.x/flow_v0.17.x-/bitcoinjs-lib_v2.x.x.js), or using the flow-typed CLI:

``` bash
npm install -g flow-typed
flow-typed install -f 0.27 bitcoinjs-lib@2.2.0
```

These definitions are maintained by [@runn1ng](https://github.com/runn1ng).


## Examples
The below examples are implemented as integration tests, they should be very easy to understand.
Otherwise, pull requests are appreciated.
Some examples interact (via HTTPS) with a 3rd Party Blockchain Provider (3PBP).

- [Generate a random address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L22)
- [Generate an address from a SHA256 hash](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L29)
- [Import an address via WIF](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L40)
- [Generate a 2-of-3 P2SH multisig address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L47)
- [Generate a SegWit address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L60)
- [Generate a SegWit P2SH address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L67)
- [Generate a SegWit 3-of-4 multisig address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L76)
- [Generate a SegWit 2-of-2 P2SH multisig address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L90)
- [Support the retrieval of transactions for an address (3rd party blockchain)](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L104)
- [Generate a Testnet address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L123)
- [Generate a Litecoin address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L133)
- [Create a 1-to-1 Transaction](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L13)
- [Create a 2-to-2 Transaction](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L28)
- [Create (and broadcast via 3PBP) a typical Transaction](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L47)
- [Create (and broadcast via 3PBP) a Transaction with an OP\_RETURN output](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L83)
- [Create (and broadcast via 3PBP) a Transaction with a 2-of-4 P2SH(multisig) input](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L105)
- [Create (and broadcast via 3PBP) a Transaction with a SegWit P2SH(P2WPKH) input](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L143)
- [Create (and broadcast via 3PBP) a Transaction with a SegWit P2WPKH input](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L174)
- [Create (and broadcast via 3PBP) a Transaction with a SegWit P2PK input](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L218)
- [Create (and broadcast via 3PBP) a Transaction with a SegWit 3-of-4 P2SH(P2WSH(multisig)) input](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L263)
- [Verify a Transaction signature](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/transactions.js#L304)
- [Import a BIP32 testnet xpriv and export to WIF](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L12)
- [Export a BIP32 xpriv, then import it](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L20)
- [Export a BIP32 xpub](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L31)
- [Create a BIP32, bitcoin, account 0, external address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L40)
- [Create a BIP44, bitcoin, account 0, external address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L55)
- [Create a BIP49, bitcoin testnet, account 0, external address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L71)
- [Use BIP39 to generate BIP32 addresses](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/bip32.js#L86)
- [Create (and broadcast via 3PBP) a Transaction where Alice can redeem the output after the expiry (in the past)](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/cltv.js#L43)
- [Create (and broadcast via 3PBP) a Transaction where Alice can redeem the output after the expiry (in the future)](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/cltv.js#L88)
- [Create (and broadcast via 3PBP) a Transaction where Alice and Bob can redeem the output at any time](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/cltv.js#L144)
- [Create (but fail to broadcast via 3PBP) a Transaction where Alice attempts to redeem before the expiry](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/cltv.js#L190)
- [Recover a private key from duplicate R values](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/crypto.js#L14)
- [Recover a BIP32 parent private key from the parent public key, and a derived, non-hardened child private key](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/crypto.js#L68)
- [Generate a single-key stealth address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/stealth.js#L72)
- [Generate a single-key stealth address (randomly)](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/stealth.js#L91)
- [Recover parent recipient.d, if a derived private key is leaked (and nonce was revealed)](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/stealth.js#L107)
- [Generate a dual-key stealth address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/stealth.js#L124)
- [Generate a dual-key stealth address (randomly)](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/stealth.js#L147)

If you have a use case that you feel could be listed here, please [ask for it](https://github.com/bitcoinjs/bitcoinjs-lib/issues/new)!


## Contributing
See [CONTRIBUTING.md](CONTRIBUTING.md).


### Running the test suite

``` bash
npm test
npm run-script coverage
```

## Complementing Libraries
- [BIP21](https://github.com/bitcoinjs/bip21) - A BIP21 compatible URL encoding library
- [BIP38](https://github.com/bitcoinjs/bip38) - Passphrase-protected private keys
- [BIP39](https://github.com/bitcoinjs/bip39) - Mnemonic generation for deterministic keys
- [BIP32-Utils](https://github.com/bitcoinjs/bip32-utils) - A set of utilities for working with BIP32
- [BIP66](https://github.com/bitcoinjs/bip66) - Strict DER signature decoding
- [BIP68](https://github.com/bitcoinjs/bip68) - Relative lock-time encoding library
- [BIP69](https://github.com/bitcoinjs/bip69) - Lexicographical Indexing of Transaction Inputs and Outputs
- [Base58](https://github.com/cryptocoinjs/bs58) - Base58 encoding/decoding
- [Base58 Check](https://github.com/bitcoinjs/bs58check) - Base58 check encoding/decoding
- [Bech32](https://github.com/bitcoinjs/bech32) - A BIP173 compliant Bech32 encoding library
- [coinselect](https://github.com/bitcoinjs/coinselect) - A fee-optimizing, transaction input selection module for bitcoinjs-lib.
- [merkle-lib](https://github.com/bitcoinjs/merkle-lib) - A performance conscious library for merkle root and tree calculations.
- [minimaldata](https://github.com/bitcoinjs/minimaldata) - A module to check bitcoin policy: SCRIPT_VERIFY_MINIMALDATA


## Alternatives
- [BCoin](https://github.com/indutny/bcoin)
- [Bitcore](https://github.com/bitpay/bitcore)
- [Cryptocoin](https://github.com/cryptocoinjs/cryptocoin)


## LICENSE [MIT](LICENSE)