@fastnear/seed-phrase

BIP-39 seed phrase generation and NEAR key derivation, isolated in its own package so the bip39 wordlist and HD-derivation code never bloat the zero-dep @fastnear/api core.

Derivation matches near-seed-phrase (and therefore near-cli and NEAR wallets): BIP-39 mnemonic → seed → SLIP-0010 ed25519 at m/44'/397'/0' → ed25519: key strings.

import { generateSeedPhrase, parseSeedPhrase } from "@fastnear/seed-phrase";

// Create a fresh account key + its recovery phrase.
const { seedPhrase, publicKey, privateKey } = generateSeedPhrase();

// Recover the same keys later (or on another device / tool).
const recovered = parseSeedPhrase(seedPhrase);
// recovered.publicKey === publicKey, recovered.privateKey === privateKey

Hand privateKey to near.state.updateAccountState({ accountId, privateKey }) to sign locally, or publicKey to near.createFundedTestnetAccount({ ... }) to create a funded testnet account.

API

• parseSeedPhrase(seedPhrase, derivationPath = NEAR_DERIVATION_PATH) → { seedPhrase, publicKey, privateKey }. Whitespace/casing are normalized; an invalid mnemonic throws.
• generateSeedPhrase(strength = 128) → the same shape for a fresh phrase (128 bits → 12 words, 256 → 24 words).
• NEAR_DERIVATION_PATH — "m/44'/397'/0'".