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Bitcoin developers are ready with quantum-resistant solutions, expected to upgrade within 5 years. You can also take immediate measures to guard against quantum attacks: Use addresses starting with bc1q (Bech32, preferred) or those starting with 3 (P2SH). Avoid using addresses starting with 1 (traditional P2PKH) or bc1p (P2TR, Taproot). Once an address has sent BTC, its public key will be exposed (addresses that have only received BTC are safe). In this case, abandon that address and switch to a new one. Most Bitcoin wallets (such as Sparrow Wallet or Electrum) default to using an address only once.