Robuta

https://arstechnica.com/information-technology/2018/04/new-hacks-siphon-private-cryptocurrency-keys-from-airgapped-wallets/
Apr 24, 2018 - Beware of smartphones and cameras around wallets storing your digital coin.
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https://github.com/johnshearing/PrivateKeyVault
Make Instructions: Airgapped raspberry pi computer for working with blockchains featuring LUKS full disk encryption and using qr-codes to pass encrypted files...
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https://github.com/cryptoadvance/specter-diy
DIY airgapped hardware wallet that uses QR codes for communication with the host - cryptoadvance/specter-diy
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https://bitcointalk.org/index.php?topic=5361456.0
AirGapped Hardware Wallets
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