A BIP32 compatible library written in TypeScript with transpiled JavaScript committed to git.
TypeScript
import * as bip32 from 'bip32';
import { BIP32Interface } from 'bip32';
let node: BIP32Interface = bip32.fromBase58('xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHi');
let child: BIP32Interface = node.derivePath('m/0/0');
// ...NodeJS
let bip32 = require('bip32')
let node = bip32.fromBase58('xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHi')
let child = node.derivePath('m/0/0')
// ...LICENSE MIT
A derivation (and extraction for modularity) of the HDWallet/HDNode written and tested by bitcoinjs-lib contributors since 2014.