Wasabi + Cold Card ~ Air-Gapped Private Bitcoin Storage

## Podcast Summary: Wasabi + Cold Card - Air-Gapped Bitcoin Storage

This podcast episode dives deep into setting up a highly secure and private Bitcoin storage system using a combination of Wasabi Wallet and a Coldcard hardware wallet. The core principle is an air-gapped setup, meaning the private keys never leave the Coldcard device, drastically reducing the risk of compromise. The process leverages a microSD card for transferring data between the computer and the Coldcard, eliminating the need for a direct USB connection and enhancing security. The hosts emphasize that this is a "privacy maximalist" setup, ideal for those prioritizing the highest levels of security and privacy in their Bitcoin holdings. They encourage listeners to embrace these tools and actively utilize them to bolster their own Bitcoin security.

1. Main Topics Discussed:

• Air-Gapped Cold Storage Setup: Creating a system where private keys remain isolated on the Coldcard hardware wallet.
• Wasabi Wallet Integration: Utilizing Wasabi Wallet to generate a "skeleton" wallet file and manage transaction building.
• MicroSD Card Transfer: Employing a microSD card for secure data transfer between the computer and Coldcard.
• Partially Signed Bitcoin Transactions (PSBTs): Leveraging PSBTs for secure communication and transaction signing. Wasabi can handle either the hex string or the final signed PSPT for broadcasting.
• Transaction Broadcasting: Demonstrating the process of broadcasting signed transactions via Wasabi to Bitcoin full nodes.
• CoinJoin Integration: Utilizing CoinJoin (Coin Joint Stacking Sets, received every Monday) for enhanced privacy.
• Coldcard Version 1.1.6: Highlighting a specific Coldcard firmware version for streamlined Wasabi integration.
• Privacy Preservation: Maintaining privacy even without running a full Bitcoin node by downloading blocks from peer-to-peer networks.
• Transaction Verification: The Coldcard displays detailed transaction information before signing, allowing for thorough verification.

2. Key Quotes:

• "This is the privacy maximalist set up for a very secure cold storage."
• "The private keys never leave that device."
• "This is fantastic, a complete air-gapped, set up with a hyper, hyper, hyper secure hardware secure module, open source, Libre, Bitcoin only, device, CypherPunk is fuck so to say."
• "These are the tools that we have at our disposal, well, it is up to us to actually go out and use them."

3. People Mentioned:

• Hosts: (Names not specified) - Address listeners as "Peers" throughout the segment.
• No other specific individuals are named.

4. Bitcoin Price (if mentioned):

• Testnet mixing coin: 0.005 Bitcoin
• Transaction cost: 0.002 Bitcoin (0.0002 BTC)
• Transaction fee: 286 Satoshi

Tools Mentioned:

• Cold Card (hardware wallet)
• Wasabi Wallet (Bitcoin wallet with privacy features)
• Tour (network used for broadcasting transactions)
• Coin Joint Stacking Sets (for CoinJoin)