eth-beacon-genesis

A tool for generating Ethereum consensus layer (beacon chain) genesis states for development and testing networks.

Features

• Generate beacon chain genesis states from execution layer genesis and validator configurations
• Support for all forks up to Electra
• Support for validator onboarding via mnemonics or direct key imports
• Configurable genesis parameters
• Output in both SSZ and JSON formats

Installation

go install github.com/ethpandaops/eth-beacon-genesis@latest

Or build from source:

git clone https://github.com/ethpandaops/eth-beacon-genesis
cd eth-beacon-genesis
go build ./cmd/eth-beacon-genesis

Usage

Basic usage to generate a devnet genesis state:

eth-beacon-genesis devnet \
  --eth1-config genesis.json \
  --config config.yaml \
  --mnemonics mnemonics.yaml \
  --state-output genesis.ssz

Command Line Options

• --eth1-config: Path to execution layer genesis config (required)
• --config: Path to consensus layer config (required)
• --mnemonics: Path to file containing validator mnemonics
• --additional-validators: Path to file with additional genesis validators
• --state-output: Output path for SSZ genesis state
• --json-output: Output path for JSON genesis state
• --quiet: Suppress output

Configuration Files

Execution Layer Genesis (genesis.json)

    {
      "config": {
        "chainId": 1337,
        "homesteadBlock": 0
      },
      "nonce": "0x0",
      "timestamp": "0x0",
      "extraData": "0x",
      "gasLimit": "0x1c9c380",
      "difficulty": "0x0",
      "mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
      "coinbase": "0x0000000000000000000000000000000000000000",
      "alloc": {}
    }

Consensus Layer Config (config.yaml)

    PRESET_BASE: "mainnet"
    CONFIG_NAME: "devnet"

    # Genesis
    MIN_GENESIS_ACTIVE_VALIDATOR_COUNT: 64
    MIN_GENESIS_TIME: 1606824000
    GENESIS_FORK_VERSION: 0x00000000
    GENESIS_DELAY: 604800

    # Forking
    ALTAIR_FORK_VERSION: 0x01000000
    ALTAIR_FORK_EPOCH: 0
    BELLATRIX_FORK_VERSION: 0x02000000
    BELLATRIX_FORK_EPOCH: 0
    CAPELLA_FORK_VERSION: 0x03000000
    CAPELLA_FORK_EPOCH: 0
    DENEB_FORK_VERSION: 0x04000000
    DENEB_FORK_EPOCH: 0
    ELECTRA_FORK_VERSION: 0x05000000
    ELECTRA_FORK_EPOCH: 0

Validator Mnemonics File

- mnemonic: ""                                             # a 24 word BIP 39 mnemonic
  start: 0                                                 # account index to start from
  count: 100                                               # number of validators to generate
  balance: 32000000000                                     # effective balance
  wd_address: "0x1234567890123456789012345678901234567890" # withdrawal address
  wd_prefix: "0x02"                                        # withdrawal credentials prefix

Development

Requirements

• Go 1.22+
• Make

Building

make build

Testing

make test

License

Apache License 2.0