---

name: bitcoin-libraries-scure-btc-signer description: | @scure/btc-signer: modern audited Bitcoin signer in TypeScript. Pure functional, minimal dependencies, browser-friendly. USE WHEN: building modern web/mobile Bitcoin apps, evaluating bitcoinjs-lib alternative. allowed-tools: Read, Grep, Glob

@scure/btc-signer

Modern Bitcoin library by Paul Miller (paulmillr.com). Audited by Trail of Bits. Smaller, cleaner API than bitcoinjs-lib.

Repo: github.com/paulmillr/scure-btc-signer.

Install

npm install @scure/btc-signer

Quick examples

Address generation

import * as btc from "@scure/btc-signer";
import { hex } from "@scure/base";

const sk = hex.decode("000...01");
const pk = btc.utils.privateAdd(sk, sk);   // example
const addr = btc.WIF().encode(sk);   // WIF
const p2wpkh = btc.p2wpkh(secp.getPublicKey(sk));
console.log(p2wpkh.address);   // bc1q...

PSBT

const tx = new btc.Transaction();
tx.addInput({
    txid: "...",
    index: 0,
    witnessUtxo: { script: spk, amount: 100000n },
});
tx.addOutputAddress(destAddr, 99000n, btc.NETWORK);
tx.sign(sk);
tx.finalize();
const rawTx = tx.extract();

Taproot

const tr = btc.p2tr(internalPubkey);
console.log(tr.address);   // bc1p...

Companion

• @scure/bip32 — HD derivation.
• @scure/bip39 — mnemonic.
• @noble/curves — secp256k1 (used internally).

Compared

See bitcoinjs-lib/SKILL.md for comparison.

Use cases

• Modern browser wallets (smaller bundle).
• React Native (better browser-compat than bitcoinjs-lib).
• Server apps wanting audited library.

Common pitfalls

• Newer ecosystem; some integrations not yet ported.
• BigInt used throughout; older browsers need polyfill.

See also

• bitcoinjs-lib/SKILL.md
• mempool-js/SKILL.md