Here is an article on how to build a Bitcoin / Lightning miner from scratch using JavaScript:
Bitcoin Mining: A Beginner’s Guide
Bitcoin (BTC) is a decentralized digital currency that uses a unique algorithm to secure its network using complex mathematical calculations. It is the largest cryptocurrency by market cap and has become increasingly popular among developers and enthusiasts. In this article, we will delve into the world of Bitcoin mining using JavaScript.
What is Bitcoin Mining?
Bitcoin mining involves solving a complex mathematical puzzle that requires significant computing power to solve. This process is called “mining” because it is like finding hidden treasure – all miners compete to be the first to solve the puzzle and receive the block reward.
Algorithm: Proof of Work (PoW)
The Bitcoin algorithm, also known as Proof of Work (PoW), is designed to ensure the security of the network by requiring miners to solve a complex mathematical problem. The problem is based on the difficulty of the solution, which is calculated using a hash function and a combination of random numbers.
The general outline of the Bitcoin PoW algorithm can be summarized as follows:
- A miner creates a unique “hash” for a block of transactions.
- The miner broadcasts their hash to the network.
- The network solves a complex mathematical problem that requires significant computing power.
- The miner with the fastest solution is declared the winner and can add their block to the blockchain.
Workflow:
Here is a step-by-step overview of the workflow:
- A new transaction is broadcast to the network.
- The transaction is verified by other nodes in the network using a consensus algorithm (such as SHA-256).
- After verification, the transaction is grouped together with other transactions in a block.
- The miner creates a unique “hash” for the block.
- The miner broadcasts his hash to the network.
- Other nodes solve a mathematical problem to find the solution and add it to their local blockchain.
- The new block is added to the blockchain, securing the network.
Algorithm: SHA-256
The Bitcoin PoW algorithm uses a variant of the SHA-256 (Secure Hash Algorithm 256) hash function. This algorithm is designed to be resistant to precomputed hash functions (PCHF), which are used in many other cryptocurrencies, such as Litecoin (LTC).
Here’s how it works:
- The miner creates a unique “hash” for the block by concatenating the following:
- The header of the previous block.
- The transaction timestamp.
- The transaction amount.
- The miner broadcasts its hash to the network.
- Other nodes calculate the SHA-256 hash of each block using the concatenated data from step 1.
- If the calculated SHA-256 hash matches the expected value, it is considered valid.
Building a Miner with JavaScript
While mining Bitcoin is an impressive feat, we can’t directly copy its code. However, we can build a simple miner that demonstrates the concept. We’ll use WebAssembly (WASM) to run JavaScript code on the Ethereum blockchain, which provides a similar framework for building miners.
First, you need to set up a new Ethereum project using Remix or Truffle. Next, install the WASM-Node library:
npm install @ethers-wallets/wasmnode
Create a new contract and add some functions that mimic the Bitcoin mining workflow:
“` javascript
// miner.js
const Web3 = require(‘web3’);
const { WasmProvider } = require(‘@ethers-wallets/wasmnode’);
const provider = new Web3.providers.HttpProvider(‘
const web3 = new Web3(provider);
const BLOCK_SIZE = 32;
// Function to generate a random number
function randomNumber() {
return Math.floor(Math.