A Raspberry Pi Is Still a Computer: Why Bitcoin Needs a Purpose-Built Hardware Wallet
TL;DR: A Raspberry Pi or ESP32 may be offline, but your seed still lands in ordinary memory under software loaded from replaceable media. Swap the MicroSD or corrupt the firmware and the device can steal the seed, lie on its display, or leak the key through valid signatures. Stateless signing adds another failure: you must expose seed words or SeedQR every time you spend, often near phones and cameras. These boards are useful for learning, nodes, coordination, or one key in a multisig designed to survive its compromise. Using one as the sole key for life-changing savings is a terrible tradeoff. Use purpose-built hardware with authenticated boot, protected key storage and a transaction display backed by authenticated firmware. For most people, single-sig plus a strong BIP39 passphrase is a very valid setup. Use multisig when its added fault tolerance is worth the operational work and you can test the complete recovery.
