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Setting up a Network

It is possible to create a new network or join an existing network. This page outlines the basics for creating a new network.

The Chain Specification

The Casper node software creates a genesis block from the following input files:

  • chainspec.toml
  • accounts.toml


A version of the chainspec is downloaded by the script installed with the casper-node-launcher debian package. This script pulls the chainspec.toml file from the appropriate path defined in the network config file used (casper.conf for MainNet and casper-test.conf for TestNet).

The production version of the file from which this is based on can be found at casper-node/resources/production/chainspec.toml in the code base. To create a custom network, this file can be updated as desired. Any changes to this file will result in a different genesis hash. Refer to the file itself for detailed documentation on each of the variables in the file.


This file contains the genesis validator set information, starting accounts and associated balances and bond amounts.

If an account is not bonded at genesis, specify a 0 for the bond amount.

Similar to the chainspec.toml, this is pulled from the appropriate path defined in the network config file used.