wallet

@decryption/wallet

BIP39 mnemonics, BIP32 derivation and address encoding — entirely offline. This package has no chain registry, no RPC client and no transaction signing: it turns a mnemonic into addresses and stops there.

Installation

npm install @decryption/wallet

Usage

import { createWallet, deriveAccounts, assertValidMnemonic } from '@decryption/wallet';

const { mnemonic, accounts } = createWallet(['cosmoshub', 'osmosis', 'ethereum'], 24);
// accounts[0] => { network: 'cosmoshub', path: "m/44'/118'/0'/0/0", address: 'cosmos1…', publicKey: '02…' }

assertValidMnemonic(userInput); // throws MnemonicError naming the actual problem
const restored = deriveAccounts(userInput, ['juno'], { account: 1, index: 3 });

Chains that are not built in — most cosmos-family chains differ only by prefix and coin type:

import { defineNetwork, deriveAccount } from '@decryption/wallet';

const dydx = defineNetwork({
  id: 'dydx',
  name: 'dYdX',
  coinType: 118,
  addressEncoding: 'bech32',
  prefix: 'dydx',
});

deriveAccount(mnemonic, dydx);

Built-in networks

Network	Coin type	Address
cosmoshub, osmosis, juno, stargaze, akash, celestia	118	bech32
secret	529	bech32
terra	330	bech32
ethereum	60	EIP-55 checksummed hex
bitcoin	0	bech32 P2WPKH

Mnemonics

import { createMnemonic, mnemonicToBytes, bytesToMnemonic } from '@decryption/wallet';

createMnemonic(12);           // 12/15/18/21/24 words
mnemonicToBytes(mnemonic);    // raw entropy, checksum verified
bytesToMnemonic(entropy);

assertValidMnemonic distinguishes the three failure modes users actually hit — wrong word count, a word outside the wordlist, and a failed checksum — so a UI can say which word is wrong instead of "invalid mnemonic".

Private keys

deriveAccount never returns private material and wipes the HD node before returning. When a private key is genuinely needed, ask for it explicitly and zero it when you are done:

import { derivePrivateKey } from '@decryption/wallet';

const key = derivePrivateKey(mnemonic, 'cosmoshub');
try {
  /* … */
} finally {
  key.fill(0);
}