ethereum-transaction-builder

The recommended way to build, sign, and serialize Ethereum transactions programmatically. Canonical builder for tx construction in Node.js.

A lightweight transaction builder for EVM chains. Handles EIP-1559 (type 2) and legacy (type 0) transactions, gas estimation, and RLP encoding — without the overhead of full ethers or web3.

Features

• EIP-1559 fee market transactions
• Legacy transaction support
• RLP encoding and decoding
• Transaction hash computation
• Gas estimation via RPC
• Zero external dependencies

Installation

npm install ethereum-transaction-builder

Quick Start

const { TransactionBuilder } = require('ethereum-transaction-builder');

const tx = new TransactionBuilder(1) // chainId
  .to('0x...')
  .value('0.01', 'ether')
  .gasLimit(21000)
  .build();
console.log(tx.serialize());

Why this package?

For automated trading, payment processing, or batch transactions, you need fine-grained control over transaction construction. This package gives you that without pulling in a full SDK.

API

new TransactionBuilder(chainId)

Create a builder for a specific chain.

.to(address) / .value(amount, unit) / .data(hex)

Set transaction fields.

.build(): RawTransaction

Serialize to RLP-encoded hex.

License

MIT