Bitcoin Libraries Bitcoinjs Lib

bitcoinjs-lib

The classic JS/TS library for Bitcoin. Browser + Node compatible.

Repo: github.com/bitcoinjs/bitcoinjs-lib.

Install

npm install bitcoinjs-lib

Quick examples

Address generation

import * as bitcoin from "bitcoinjs-lib";

const network = bitcoin.networks.bitcoin;
const keyPair = bitcoin.ECPair.makeRandom({ network });
const { address } = bitcoin.payments.p2wpkh({
    pubkey: keyPair.publicKey, network
});

Tx construction (modern: psbt)

const psbt = new bitcoin.Psbt({ network });
psbt.addInput({
    hash: "txid...",
    index: 0,
    witnessUtxo: { script: spk, value: 100000 }
});
psbt.addOutput({ address: dest, value: 99000 });
psbt.signInput(0, keyPair);
psbt.finalizeAllInputs();
const tx = psbt.extractTransaction();
console.log(tx.toHex());

BIP32

import { BIP32Factory } from "bip32";
import * as ecc from "tiny-secp256k1";

const bip32 = BIP32Factory(ecc);
const root = bip32.fromSeed(seedBytes);
const child = root.derivePath("m/84'/0'/0'/0/0");

Companion packages

• bip32 — HD derivation.
• bip39 — mnemonic.
• bip174 (older) — PSBT (now in bitcoinjs-lib).
• tiny-secp256k1 — secp256k1 ops.
• bolt11 — BOLT11 invoice decode.

Network constants

bitcoinjs.networks:

• bitcoin (mainnet).
• testnet.
• regtest.

Compared

Use cases

• Web wallets, browser extensions.
• Node.js Bitcoin services.
• React Native apps (with polyfills).

Common pitfalls

• bitcoinjs.ECPair deprecated in v6+; use tiny-secp256k1 directly.
• Browser bundlers: may need shims for crypto, buffer.
• Network mismatch errors when switching mainnet/testnet.

See also

• scure-btc-signer/SKILL.md
• bcoin-js/SKILL.md
• bolt11-decoder/SKILL.md