ethereum/go-ethereum

Go Ethereum, commonly called Geth, is the official Go programming language implementation of the Ethereum blockchain protocol. Ethereum is a decentralized network where participants can transfer a cryptocurrency called Ether and run self-executing programs called smart contracts. Geth is the software that lets you actually participate in this network by running a node, which means your computer downloads and verifies the blockchain's transaction history and stays synchronized with thousands of other nodes around the world. Geth can operate in several modes: as a full node that processes recent transactions without storing the entire history, as an archive node that keeps every historical state ever recorded, or as a light node that trusts other nodes for most data and only verifies what it needs. It exposes an API over HTTP, WebSocket, or a local socket so other applications, like wallets or decentralized apps, can query blockchain data and send transactions. The repository also ships several developer tools, including a standalone signing tool called Clef, a utility for running Ethereum smart contract bytecode in isolation for debugging, and a code generator that turns smart contract definitions into type-safe Go packages. You would use Geth if you want to run your own Ethereum node rather than relying on a third-party service, which gives you privacy, independence, and the ability to verify transactions yourself. It is also the entry point for developers building applications on Ethereum who need a local or private test network. Running a full sync on the main network requires a powerful machine with at least 1 TB of fast storage. The tech stack is entirely Go, with some C components, and it is built with the standard Go toolchain.