FAQ
Direct answer: Frequently asked questions about CKBunker, COLDCARD HSM mode, Tor, source code, and device support.
Is CKBunker a hardware wallet?
No. CKBunker is a helper application. The COLDCARD is the hardware wallet and HSM boundary.
Does CKBunker hold my seed?
No. Private keys remain on the COLDCARD. CKBunker coordinates requests and approvals.
Can it work over Tor?
Yes. CKBunker can expose its web interface as a Tor hidden service when Tor is running on the same host.
Does it support COLDCARD Q?
Current COLDCARD HSM documentation says HSM mode is not provided on COLDCARD Q. Verify current firmware support before deployment.
What is HSM?
HSM means Hardware Security Module. In this context, it means using COLDCARD as a policy-constrained signer that can approve allowed requests without normal interactive confirmation for every transaction.
Where is the source code?
The CKBunker source repository is https://github.com/Coldcard/ckbunker.