A Node.js CLI tool for managing Bitcoin wallets using BIP39 mnemonics and BlockCypher API.

• Create Wallet - Generate new Bitcoin addresses
• Import Wallet - Import wallets from BIP39 mnemonic phrases
• List Wallets - View all stored wallets
• Check Balance - Get wallet balance from blockchain
• Transaction History - Fetch wallet transactions
• Get Unused Address - Find addresses available for receiving funds

• Node.js (ES6 Modules)
• bitcore-lib (Bitcoin cryptography)
• bitcore-mnemonic (BIP39 support)
• axios (HTTP client)
• BlockCypher API (Bitcoin testnet)

git clone https://github.com/tanishchugh01/blockchain-wallets.git
cd blockchain-wallets
npm install

Create a .env file with your BlockCypher token:

BLOCK_CYPHER_TOKEN=your_token_here

Get a free token at blockcypher.com

npm start

Runs a demo showing all features working with actual blockchain data.

src/
├── index.js              # Main demo
├── api/                  # 6 wallet features
│   ├── createWallet.js
│   ├── importWallet.js
│   ├── listAllWallets.js
│   ├── getWalletBalance.js
│   ├── getWalletTransactions.js
│   ├── getUnusedAddress.js
│   └── index.js
├── configs/              # Configuration
│   ├── blockCypher.js
│   └── CONSTANTS.js
└── methods/              # Utilities
    ├── deriveAddressFromMnemonic.js
    ├── getAddressBalance.js
    ├── getWalletInfo.js
    ├── loadWallets.js
    └── saveWallets.js

• Validates mnemonic phrases using bitcore-mnemonic
• Derives addresses using BIP44 standard (m/0'/0/0)
• Supports 12, 15, 18, 21, and 24-word mnemonics

• Creates testnet addresses (prefix 'm' or 'n')
• Uses BlockCypher API for address generation
• Stores address metadata locally

• Wallets stored in storage/wallets.json
• Simple JSON persistence
• Auto-creates storage directory

• BlockCypher API for blockchain queries
• Bitcoin testnet endpoint: https://api.blockcypher.com/v1/btc/test3
• Token-based authentication

• Mnemonic validation
• Wallet existence checks
• Graceful API error handling

========================================
  Bitcoin Wallet Management System
========================================

3️⃣  Importing wallet from BIP39 mnemonic...
✅ Wallet Imported: TestMnemonic
   Address: n28VbW7cyn2Bj9b7iCH6U34t58jzsiuEig

4️⃣  Listing all wallets...
✅ Total Wallets: 1
   1. TestMnemonic (n28VbW7cyn2Bj9b7iCH6U34t58jzsiuEig)

5️⃣  Checking wallet balance...
Balance: 0 satoshi

6️⃣  Fetching wallet transactions...
Transactions of TestMnemonic:
Transaction 1:
   Confirmations: 3574879
   Value: 32443500 satoshi
   Time: 29/10/2017, 12:35:24 am

7️⃣  Getting unused address...
Unused Address: n28VbW7cyn2Bj9b7iCH6U34t58jzsiuEig

========================================
  All tests completed successfully!
========================================

• ✅ Private keys never stored locally
• ✅ BlockCypher token in .env (not committed)
• ✅ Bitcoin testnet only (no real funds)
• ✅ Input validation on mnemonics