Bitcoin Ciphers

Krux

Online · Nationwide

Krux is open-source firmware that turns off-the-shelf Kendryte K210 devices into airgapped bitcoin transaction signers, commonly used as one of the signers in a multisig setup. It also provides tooling for creating, encrypting and recovering mnemonic backups.

Services

  • Air-gapped QR signing
  • Runs on off-the-shelf devkits
  • Multisig
  • Seed backup tooling
  • PSBT support
  • DIY airgapped signing device

Highlights

  • #open-source
  • #diy
  • #air-gapped
  • #bitcoin-only
  • #multisig

Source: Official project site. Last checked 2026-09-18. Spot an error? Tell us.

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