Introducing Bitcoin Guard

This initiative is sparked by an alarming trend of physical attacks on individuals for their Bitcoin, which prompted the development of this project. The core idea behind Bitcoin Guard is to alter the game theory outcomes in favor of the victim by increasing the risk and reducing the reward for the attacker. This is achieved through technical and physical security measures that make it challenging for attackers to access the victim's funds without being detected or hindered.

The project introduces a lightweight signaling protocol within a Bitcoin address that enables users to lock their wallets in case of an emergency, preventing unauthorized transactions. This protocol is part of draft Bitcoin Improvement Proposals (BIPs) and is designed to be implemented in both self-custodial wallets and centralized exchanges. It includes several components such as the Bitcoin Guard Desktop and Mobile Applications, the Guardian Address Signal Protocol Draft (GASPv1) BIP, and the Guardian Wallet Implementation Draft BIP. The user experience is streamlined, allowing individuals familiar with hardware wallets to use Bitcoin Guard effectively without needing to understand the specifics of the underlying protocol.

The mobile application offers a suite of security features that can be configured by the user. For instance, in the event of a device theft or if the user is incapacitated, trusted contacts can broadcast a pre-signed Lock, activating the Guardian Lock. The app also features a Countdown Timer for automatic signal broadcasting, a Rage PIN that prevents unauthorized access by simulating a decoy wallet, and Voice Activation for hands-free operation. Integration with third-party services like Telegram and Twilio is planned to alert trusted contacts during an emergency. Additionally, manual activation of the Guardian Lock is available for users who perceive an imminent threat.

On the desktop front, the Bitcoin Guard Application simplifies protocol implementation and management of the Guardian Address. It supports full lifecycle operations from setup to signals, with a user-friendly interface that guides through each step. The application works seamlessly with hardware wallets, ensuring secure transaction broadcasting. Users interested in custom activation methods can export transaction hex data for personal use.

The effectiveness of Bitcoin Guard has been demonstrated through a complete implementation in an Electrum fork, with successful testnet broadcasts confirming the prevention of unauthorized spending when locked. Detailed technical specifications and operational insights are provided in the supporting documentation available online.

For further exploration and hands-on experience with Bitcoin Guard's capabilities, interactive prototypes are accessible for both mobile and desktop applications, alongside the project's GitHub repository and technical details.