Use cases
Direct answer: CKBunker use cases for remote signing, geographically separated multisig, warm-wallet freeze, executive approvals, and Storage Locker workflows.
CKBunker is for advanced teams and operators that need policy-controlled signing without bringing every signer to the hardware wallet every time.
Small payments with limits
Permit routine low-value payments with user authorization and velocity limits.
Geographic separation
Keep the COLDCARD in one location while remote signers review and approve PSBTs over Tor.
Warm-wallet freeze
Whitelist one cold-storage destination so funds can be swept to safety under stress.
Executive approvals
Require a threshold of named users before treasury transactions are signed.
Meet-me-in-the-Bunker
Gather multiple operators around the same PSBT state for coordinated remote signing.
Storage Locker
Use COLDCARD-backed secret storage for Bunker settings such as encrypted onion-service keys.
When not to use it
- You do not yet understand PSBTs or COLDCARD policy controls.
- You cannot physically secure the host and hardware wallet.
- You need a beginner hot wallet or exchange withdrawal helper.
- Your deployment depends on unsupported device models or untested dependency versions.