/SavjeeCoin

A simple blockchain in Javascript. For educational purposes only.

Primary LanguageJavaScriptMIT LicenseMIT

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SavjeeCoin

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⚠️ For education purposes only. This is by no means a complete implementation and it is by no means secure!

Features

  • Simple proof-of-work algorithm
  • Verify blockchain (to prevent tampering)
  • Generate wallet (private/public key)
  • Sign transactions

🏁 Getting Started

Install library

npm install --save savjeecoin

Generate a keypair

To make transactions on this blockchain you need a keypair. The public key becomes your wallet address and the private key is used to sign transactions.

const EC = require('elliptic').ec;
const ec = new EC('secp256k1');

const myKey = ec.genKeyPair();

The myKey object now contains your public & private key:

console.log('Public key:', myKey.getPublic('hex'));
console.log('Private key:', myKey.getPrivate('hex'));

Create a blockchain instance

Now you can create a new instance of a Blockchain:

const {Blockchain, Transaction} = require('savjeecoin');

const myChain = new Blockchain();

Adding transactions

// Transfer 100 coins from my wallet to "toAddress"
const tx = new Transaction(myKey.getPublic('hex'), 'toAddress', 100);
tx.sign(myKey);

myChain.addTransaction(tx);

To finalize this transaction, we have to mine a new block. We give this method our wallet address because we will receive a mining reward:

myChain.minePendingTransactions(myKey.getPublic('hex'));

📽 Video tutorial

This source code comes from my video series on YouTube. You can check them here:

Video 1: Simple implementation Video 2: Adding Proof-of-work
Video 3: Mining rewards & transactions Video 4: Signing transactions
Video 5: Building a front-end in Angular