Chains

Chains are sovereign networks within Lux that define their own rules for membership, consensus parameters, and virtual machine implementations. Every chain is validated by a dynamic set of validators who also validate the Lux Primary Network.

What Are Chains?

A chain is an independent network with its own:

Validator set - Choose which validators participate
Consensus parameters - Tune finality speed and throughput
Virtual machine - Run EVM, Sovereign L1 EVM, or a fully custom VM
Gas token - Use LUX or a custom native token
Access control - Public or permissioned networks

Chains do not share state or execution with other chains. They are isolated environments that leverage the Lux Primary Network for validator coordination and security.

Create a Chain

Using the CLI

Install the Lux CLI

npm install -g @luxfi/cli

Create the Chain Configuration

lux chain create my-chain

You will be prompted to select:

VM type: Sovereign L1 EVM (recommended), Custom
Chain ID: A unique EVM chain identifier
Gas configuration: Fee structure and limits
Airdrop: Optional initial token distribution

Deploy to Local Network

lux chain deploy my-chain --local

This starts a local multi-node network with your chain for testing.

Deploy to Testnet

lux chain deploy my-chain --testnet

This creates the chain on-chain and registers validators on the Lux testnet.

Deploy to Mainnet

lux chain deploy my-chain --mainnet

Sovereign L1 EVM Configuration

Sovereign L1 EVM is the most common VM for chains. It is a configurable fork of the Lux C-Chain EVM.

Genesis Configuration

{
  "config": {
    "chainId": 12345,
    "feeConfig": {
      "gasLimit": 15000000,
      "targetBlockRate": 2,
      "minBaseFee": 25000000000,
      "targetGas": 15000000,
      "baseFeeChangeDenominator": 36,
      "minBlockGasCost": 0,
      "maxBlockGasCost": 1000000,
      "blockGasCostStep": 200000
    },
    "allowFeeRecipients": false
  },
  "alloc": {
    "0xYourAddress": {
      "balance": "0x52B7D2DCC80CD2E4000000"
    }
  },
  "nonce": "0x0",
  "timestamp": "0x0",
  "gasLimit": "0xE4E1C0"
}

Key Configuration Options

Option	Description	Default
`chainId`	Unique chain identifier	Required
`gasLimit`	Maximum gas per block	15,000,000
`targetBlockRate`	Target seconds between blocks	2
`minBaseFee`	Minimum gas price in Wei	25 Gwei
`allowFeeRecipients`	Allow validators to collect fees	false

Precompiles

Enable optional precompiles in your chain genesis:

{
  "config": {
    "contractNativeMinterConfig": {
      "blockTimestamp": 0,
      "adminAddresses": ["0xAdminAddress"]
    },
    "contractDeployerAllowListConfig": {
      "blockTimestamp": 0,
      "adminAddresses": ["0xAdminAddress"]
    },
    "txAllowListConfig": {
      "blockTimestamp": 0,
      "adminAddresses": ["0xAdminAddress"]
    }
  }
}

Validator Management

Adding Validators

Validators validate networks, not chains. Chains live on a network and inherit the network's validator set. To add a validator to a network — whether the Lux primary network or your own sovereign L1's primary network — use AddValidatorTx (the universal "add validator to a network" transaction). The CLI helper:

lux network addValidator my-network \
  --node-id=NodeID-... \
  --stake-amount=2000 \
  --start-time="2025-01-01T00:00:00Z" \
  --end-time="2026-01-01T00:00:00Z"

Validator Requirements

Requirement	Value
Primary Network stake	Minimum 2,000 LUX
Network stake	Defined by network creator
Uptime	Network-specific (recommended 80%+)
Duration	Must overlap with Primary Network validation period

Custom Virtual Machines

For use cases that require non-EVM execution, you can build a custom VM.

A Lux VM implements the block.ChainVM interface:

type ChainVM interface {
    Initialize(ctx *consensus.Context, db database.Database, genesisBytes []byte, ...) error
    BuildBlock() (Block, error)
    ParseBlock([]byte) (Block, error)
    GetBlock(ids.ID) (Block, error)
    SetPreference(ids.ID) error
    LastAccepted() (ids.ID, error)
}

Custom VMs are powerful but require careful design. For most applications, Sovereign L1 EVM with custom precompiles provides sufficient flexibility without the complexity of a fully custom VM.

Chain Architecture

┌──────────────────────────────────────────────┐
│               Primary Network                │
│  ┌──────────┬──────────┬──────────┐         │
│  │ P-Chain  │ X-Chain  │ C-Chain  │         │
│  └──────────┴──────────┴──────────┘         │
│        Validators: {A, B, C, D, E}           │
└──────────────────────────────────────────────┘
           │                    │
    ┌──────┴──────┐     ┌──────┴──────┐
    │  Chain-1   │     │  Chain-2   │
    │  EVM-based  │     │  Custom VM  │
    │  Validators:│     │  Validators:│
    │  {A, B, C}  │     │  {B, D, E}  │
    └─────────────┘     └─────────────┘

Use Cases

DeFi Chains

High-throughput chains optimized for decentralized finance with custom gas tokens and fee structures.

Gaming Networks

Low-latency chains with fast block times and permissioned validator sets for predictable performance.

Enterprise Chains

Permissioned chains with transaction allow-lists and KYC-compliant validator sets.

AI Compute

Specialized chains for decentralized AI inference and training coordination.

Chains

Chains

What Are Chains?

Create a Chain

Using the CLI

Install the Lux CLI

Create the Chain Configuration

Deploy to Local Network

Deploy to Testnet

Deploy to Mainnet

Sovereign L1 EVM Configuration

Genesis Configuration

Key Configuration Options

Precompiles

Validator Management

Adding Validators

Validator Requirements

Custom Virtual Machines

Chain Architecture

Use Cases

DeFi Chains

Gaming Networks

Enterprise Chains

AI Compute

Further Reading

On this page