Your will, protected by math — not promises

Three layers of protection

You don't need to understand cryptography to use DocSats. But you should understand why your will is safe. Think of it as three unbreakable layers:

How your will goes from conversation to Bitcoin

How your family gets access — and not a second too early

The biggest question in estate planning: how do your heirs read the will when the time comes, without being able to peek early?

DocSats uses a dead man's switch. Here's how it works:

What we guarantee

What's actually inscribed on Bitcoin

Only a small proof object (~150 bytes) is inscribed — never your actual will content. Here's the exact schema:

{
  "v":    2,                          // Schema version
  "prev": "inscription_id_of_v1",     // Previous version (null if first)
  "t":    1708234567,                  // Unix timestamp
  "cid":  "QmX7b3f...encrypted_ipfs",  // IPFS content identifier
  "h":    "a3f8c2...sha256_hash",      // SHA-256 of encrypted file
  "uid":  "hashed_user_id",            // Anonymized user identifier
  "app":  "docsats.com",               // Application identifier
  "sig":  "docsats_ed25519_signature"  // Authenticity signature
}

Why this matters: The h (hash) field is the critical piece. It's a unique fingerprint of your encrypted document. Change even a single character of the document and the hash completely changes. Compare the hash on Bitcoin to a fresh hash of the IPFS file — if they match, zero tampering has occurred.

The sig field prevents forgery. Anyone can inscribe data on Bitcoin, but only DocSats can produce a valid signature. The verification page checks this signature against DocSats' published public key.

The prev field creates a version chain. If you update your will, the new inscription references the old one — creating an auditable trail of every version, with timestamps proving exactly when each change was made.

Client-side encryption architecture

// 1. Generate random 256-bit key in the browser
key = crypto.subtle.generateKey("AES-GCM", 256)

// 2. Generate random initialization vector
iv = crypto.getRandomValues(12 bytes)

// 3. Encrypt the will document
encrypted = crypto.subtle.encrypt({AES-GCM, iv}, key, will)

// 4. Generate SHA-256 hash of encrypted output
hash = SHA-256(encrypted)

// 5. Upload encrypted blob to IPFS → get CID
// 6. Send {cid, hash} to DocSats → inscribe on Bitcoin
// ⚠️ Plaintext will NEVER leaves the browser

AES-256-GCM is an authenticated encryption algorithm. "Authenticated" means it detects any tampering with the ciphertext — not just unauthorized reading, but unauthorized modification. This is the same algorithm recommended by NIST and used by the U.S. government for classified information.

Web Crypto API is a native browser API — no third-party libraries needed. The encryption key is generated using cryptographically secure random number generation built into your browser. It never touches our servers in plaintext form.

Why Bitcoin — and not any other chain

Your will needs to outlive you. That means it needs the most durable infrastructure on the planet.

Bitcoin is the only network where we can say with near-certainty: data inscribed today will still be readable in 50 years. For estate planning, that's not a nice-to-have — it's the whole point.

What if DocSats disappears?

We built DocSats to survive without us. Here's why you're never dependent on us existing:

Will updates and version history

Life changes. Marriages, births, divorces, new assets — your will should change too. DocSats handles updates cleanly:

Each update creates a new inscription that references the previous one. This creates a verifiable chain:

v1 — Jan 15, 2026  →  inscription_abc123
   ↓ updated
v2 — Mar 20, 2026  →  inscription_def456  (prev: abc123)
   ↓ updated
v3 — Sep 8, 2026   →  inscription_ghi789  (prev: def456)

The latest inscription is always the valid will.
The full chain proves every change with timestamps.

This is actually a massive advantage over paper wills. In a traditional dispute, someone might claim "this isn't the latest version" or "the date was forged." With DocSats, every version is cryptographically timestamped on Bitcoin. The chain of updates is publicly verifiable and impossible to forge.