The good news is, in 2012 the developer Pieter Wuille established the BIP32 specification at The bottom in the hierarchical deterministic wallets. Together with it, Pieter established a mathematical perform to create a master key from which to derive all other keys within a deterministic way. A simple backup program https://bookmarkmargin.com/story19473376/the-definitive-guide-to-bip39-seed-phrase