Bitcoin Inheritance Planner

# Example Bitcoin Script with CLTV (absolute timelock)
# This locks funds until block height 800000 (approximately year 2025)

<800000> CHECKLOCKTIMEVERIFY DROP
<public key> CHECKSIG

# In Electrum, you can create a transaction with a timelock:
electrum payto --locktime=800000 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa 0.1
                                        

# Example Bitcoin Script with CSV (relative timelock)
# This locks funds for 52560 blocks (approximately 1 year) after the output is confirmed

<52560> CHECKSEQUENCEVERIFY DROP
<public key> CHECKSIG

# In Bitcoin Core, you can create a transaction with a relative timelock:
bitcoin-cli createrawtransaction '[{"txid":"previous_tx_id","vout":0}]' '{"1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa":0.1}' 52560
                                        

# Example implementation using a service like Casa Keymaster:
# 1. Set up a 3-of-5 multi-signature wallet
# 2. Configure the inheritance plan in Casa
# 3. Set the waiting period (e.g., 3 months)
# 4. Designate recovery key holders

# Self-hosted solution using a script (pseudocode):
#!/bin/bash
# This script should be run periodically (e.g., via cron)

LAST_CHECK_FILE="/path/to/last_check.txt"
CURRENT_TIME=$(date +%s)
# 6 months in seconds
TIMEOUT=$((60*60*24*30*6))

if [ -f "$LAST_CHECK_FILE" ]; then
  LAST_CHECK=$(cat $LAST_CHECK_FILE)
  ELAPSED=$((CURRENT_TIME - LAST_CHECK))
  
  if [ $ELAPSED -gt $TIMEOUT ]; then
    # Execute the inheritance plan
    # This could send an email to beneficiaries with instructions
    # or trigger a pre-signed transaction
    echo "Executing inheritance plan..."
    # Add your code here
  fi
else
  # First run, just record the time
  echo $CURRENT_TIME > $LAST_CHECK_FILE
fi

# Update the last check time
echo $CURRENT_TIME > $LAST_CHECK_FILE
                                        

# Example Bitcoin Script combining CLTV with multi-signature
# This requires 2-of-3 signatures after block height 800000

IF
  <800000> CHECKLOCKTIMEVERIFY DROP
  <public key 1> CHECKSIGVERIFY
  <public key 2> CHECKSIG
ELSE
  2 <public key 1> <public key 2> <public key 3> 3 CHECKMULTISIG
ENDIF

# This script allows:
# 1. Normal spending with 2-of-3 signatures before the timelock
# 2. After the timelock, only specific keys can spend (e.g., beneficiary keys)
   

# Using SLIP39 (Shamir's Secret Sharing for mnemonic codes)
# Example with the Trezor hardware wallet:

# 1. Initialize a new wallet with Shamir Backup
# 2. Choose the number of shares (e.g., 5)
# 3. Set the threshold (e.g., 3)
# 4. Distribute the shares to trusted individuals or secure locations

# Using the shamir-share command-line tool:
# Install: pip install shamir-share

# Create 5 shares with a threshold of 3:
shamir-share split -n 5 -t 3 "your_seed_phrase_here"

# Recover the secret with at least 3 shares:
shamir-share combine share1 share2 share3
                                        

# Example backup plan:

# 1. Create multiple copies of your seed phrase
# 2. Store in secure, geographically distributed locations:
#    - Home safe
#    - Bank safety deposit box
#    - With a trusted family member in another city
#    - In a secure location in another country

# For enhanced security, split the seed phrase:
# Location 1: Words 1-8
# Location 2: Words 9-16
# Location 3: Words 17-24
# Location 4: Words 1-8 (duplicate)
# Location 5: Words 9-16 (duplicate)
# Location 6: Words 17-24 (duplicate)

# Document the locations securely and ensure beneficiaries know how to access them
   

# Metal backup options:

# 1. Cobo Tablet or Cobo Tablet Plus
# Instructions:
# - Use the included punch to stamp your seed words onto metal plates
# - Secure the assembled tablet in a safe location

# 2. Coldcard Seedplate
# Instructions:
# - Stamp your seed words onto the metal plate
# - Store in a fireproof and waterproof container

# 3. Cryptosteel or Cryptosteel Capsule
# Instructions:
# - Arrange the included metal tiles to spell out your seed phrase
# - Secure the assembled device in a safe location

# 4. DIY solution with metal washers:
# - Purchase stainless steel washers
# - Use a metal stamp set to stamp one word per washer
# - Thread washers onto a steel wire or bolt
# - Secure in a fireproof container
   

# Example hybrid backup plan:

# 1. Create a 3-of-5 Shamir's Secret Sharing scheme for your seed
#    - Store shares in different locations and with trusted individuals

# 2. Create metal backups of each share
#    - Use different metal backup solutions for diversity

# 3. Create a 2-of-3 multi-signature wallet as an additional layer
#    - Store keys on different hardware wallets
#    - Back up each hardware wallet's seed using the methods above

# 4. Document the entire setup
#    - Create clear instructions for beneficiaries
#    - Store instructions securely but separately from the keys
#    - Consider encrypting the documentation with a password known to beneficiaries
   

# Electrum Command Line Examples

# Create a new standard wallet:
electrum create --wallet="standard_wallet"

# Create a multi-signature wallet:
electrum create --wallet="multisig_wallet" --multi

# Export master public key:
electrum getmpk -w "wallet_name"

# Create a transaction with timelock:
electrum payto --locktime=800000 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa 0.1 -w "wallet_name"

# Sign a transaction:
electrum signtransaction "hex_of_transaction" -w "wallet_name"

# Broadcast a transaction:
electrum broadcast "hex_of_signed_transaction"

# Create a watch-only wallet from xpub:
electrum restore "xpub..." --wallet="watch_only_wallet"
                                        

# Bitcoin Core Command Line Examples

# Create a raw transaction:
bitcoin-cli createrawtransaction '[{"txid":"previous_tx_id","vout":0}]' '{"1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa":0.1}'

# Create a transaction with locktime:
bitcoin-cli createrawtransaction '[{"txid":"previous_tx_id","vout":0}]' '{"1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa":0.1}' 800000

# Sign a transaction:
bitcoin-cli signrawtransactionwithwallet "hex_of_raw_transaction"

# Send a transaction:
bitcoin-cli sendrawtransaction "hex_of_signed_transaction"

# Create a multi-signature address:
bitcoin-cli createmultisig 2 '["public_key1", "public_key2", "public_key3"]'

# Import a watch-only address:
bitcoin-cli importaddress "address" "label" true
                                        

# Casa Keymaster
# Features:
# - 3-of-5 multi-signature setup
# - Dedicated inheritance protocol
# - Key management service
# - Mobile app for key management
# Website: https://keys.casa/

# Unchained Capital Vaults
# Features:
# - Collaborative custody multi-signature
# - Inheritance planning support
# - Key management assistance
# Website: https://unchained.com/

# Pamela Morgan's Cryptoasset Inheritance Planning Book
# A comprehensive guide to creating a Bitcoin inheritance plan
# Available on Amazon and other book retailers
   

# Trezor Model T
# Features:
# - Shamir Backup (SLIP39) support
# - Password manager
# - Multi-signature support
# Website: https://trezor.io/

# Ledger Nano X
# Features:
# - Multi-signature support via Ledger Live
# - Support for multiple apps
# - Bluetooth connectivity
# Website: https://www.ledger.com/

# Coldcard Mk4
# Features:
# - Air-gapped operation
# - Multi-signature support
# - Duress PIN feature
# - Steel backup options
# Website: https://coldcard.com/