Dead Man's Switch: How to Automate Crypto Inheritance

TL;DR: A dead man's switch is a mechanism that triggers automatically when you stop responding. Combined with Shamir's Secret Sharing, it enables trustless crypto inheritance without giving anyone premature access.

What Is a Dead Man's Switch?

The term comes from early train locomotives. Drivers had to keep a pedal pressed. If the driver fell asleep or died, the pedal would release and automatically stop the train.

In the digital world, a dead man's switch is any system that requires periodic confirmation that you are still active. If you stop confirming, it assumes something happened and takes action.

Why Crypto Needs This

The challenge with crypto inheritance is timing: - Too early: Someone could steal your funds while you are alive. - Too late: Your heirs can't find or access the keys. - Just right: Access transfers exactly when needed.

A dead man's switch solves the timing problem automatically.

How deadhand's Switch Works

The Timeline

• Day 0: You create a vault and activate the switch.
• Day 1 to 29: Nothing happens (you are presumably active).
• Day 30: We send you an email: "Are you still there?"
• Day 30 to 59: If you click the link, your timer resets to Day 0.
• Day 60: Final warning email.
• Day 90: If no response, Shard C is sent to your beneficiary.

Why 90 Days?

We chose 90 days as the default because: - It is long enough to handle vacations or hospital stays. - It is short enough that heirs do not have to wait years. - Multiple reminders prevent accidental triggers.

Note: We are working on customizable timers (30 days to 1 year) for pro users.

The Trust Model

deadhand is designed to be trustless.

What deadhand Has

• Your email address.
• Your beneficiary's email address.
• Shard C (encrypted and useless alone).

What deadhand Does Not Have

• Your seed phrase.
• Shard A (you keep this).
• Shard B (your beneficiary keeps this).
• Any ability to access your funds.

Even if deadhand were compromised, Shard C alone reveals zero information about your seed phrase.

Security Considerations

What if deadhand is hacked?

Hackers would get a database of encrypted Shard C values. Without the matching Shard A or Shard B, these are worthless. It is like having one piece of a complex puzzle: no picture emerges.

What if the email goes to spam?

We send from a verified domain with proper SPF/DKIM records. We also send multiple reminders over a 60-day period. We recommend: 1. Adding our email to your contacts. 2. Checking your spam folder once a month. 3. Setting a personal calendar reminder.

What if the switch triggers prematurely?

If you forget to check in and Shard C is sent to your beneficiary, they still cannot access your funds unless they have Shard B. If they have Shard B, you should only give it to someone you trust.

Alternative Approaches

Google Inactive Account Manager

Google offers a similar feature for Google accounts. After several months of inactivity, it can share data with contacts. But it only works for data within Google's ecosystem.

Lawyers and Wills

Traditional estate planning can include crypto instructions. But lawyers are often slow, expensive, and may not understand how to protect a seed phrase securely.

Metal Plates in a Safe

Some people stamp their seed phrase on metal and put it in a safe deposit box. This works, but it requires your heirs to find the box and have the legal right to access it.

The deadhand Advantage

We combine the best parts of these approaches:

• Automated: No manual action needed when you disappear.
• Trustless: We cannot access your funds.
• Simple: No technical knowledge required.
• Secure: Shamir's math protects against theft.
• Reversible: You can recover with Shard A and B at any time.

Real-World Scenarios

Scenario 1: You Pass Away

• Day 30: Email sent (no response).
• Day 60: Final warning (no response).
• Day 90: Shard C sent to beneficiary.
• Day 91: Beneficiary combines B+C, recovers seed, accesses funds.

Scenario 2: You are Hospitalized

• Day 30: Email sent to your inbox.
• Day 45: You recover and click the link.
• Timer resets. No shards are sent.

Scenario 3: You Forget

• Day 30: Email sent (you miss it).
• Day 60: Final warning (you notice).
• Day 61: You click the link.
• Timer resets. Crisis averted.

Getting Started

Setting up your dead man's switch takes 5 minutes:

1. Go to deadhand.xyz
2. Enter your seed phrase (client-side only).
3. Download or print Shard A and B.
4. Enter your email and beneficiary's email.
5. Activate the switch.

Cost: $0 for the first 50 early bird users. We are in public beta and building trust.

Questions? Check our FAQ or contact us.