Bip39 Npm. Firstly it is best to retail store it SEPARATELY from the seed. Having your seed plus your passphrase in exactly the same spot defeats the purpose of getting a passphrase to start with. BIP39 can be a layout implementation that lays out how copyright wallets build the list https://directmysocial.com/story3391732/bip39-wallet-https-linktr-ee-bip39-the-single-best-strategy-to-use-for-bip39-wallets