CKBunker is Coinkite's open-source software for running a Coldcard in HSM mode so transactions can be authorised over Tor according to a preset policy. It is aimed at teams and businesses that need policy-controlled signing while retaining their own keys.
Source: Official website. Last checked 2026-09-18. Spot an error? Tell us.
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Two engraved stainless steel sheets from Swiss maker Shift Crypto, holding up to 24 recovery words at 12 per sheet. An automatic puncher is included and only the first four letters of each BIP39 word need marking. Made in the EU with a two-year warranty.
Shift Crypto's heavy-duty reusable backup, built from thick stainless steel with a screw closure and tamper-evident sticker. Because it uses rearrangeable character tiles rather than punched marks, the stored phrase can be updated at any time.