Fakenet

Fakenet is Armchain's built-in local development network. Think of it as Armchain's equivalent of Hardhat Network or Ganache. It runs a private chain with auto-generated validators, pre-funded accounts, and fast block times, all with a single command.

Overview

Fakenet provides:

• Instant setup: No genesis file, single command to launch

• Deterministic keys: Auto-generated validator keys for reproducibility

• Fast parameters: 3-second empty block skip, 10-minute epochs

• Full feature set: All consensus, EVM, and PQC features active

• Pre-funded accounts: Validators start with 1 billion ARM each

Quick Start

Single Validator (PoA-like)

Single validator acting as a standalone block producer:

# Build the client
cd armchain-client
make armnode

# Run single-validator fakenet
./build/armnode --fakenet 1/1 \
  --http \
  --http.addr 0.0.0.0 \
  --http.port 4000 \
  --http.api eth,web3,net,personal,txpool,arm,dag,debug,admin \
  --http.corsdomain "*" \
  --ws \
  --ws.addr 0.0.0.0 \
  --ws.port 4500 \
  --ws.api eth,web3,net,arm \
  --allow-insecure-unlock

Your local RPC is now available at http://localhost:4000.

Multi-Validator Network

More realistic test setup with multiple validators:

# Terminal 1 - Validator 1 of 3
./build/armnode --fakenet 1/3 --port 3001 --http --http.port 4001 --http.api eth,web3,net,personal,admin,arm,dag

# Terminal 2 - Validator 2 of 3
./build/armnode --fakenet 2/3 --port 3002 --http --http.port 4002 --http.api eth,web3,net,personal,admin,arm,dag

# Terminal 3 - Validator 3 of 3
./build/armnode --fakenet 3/3 --port 3003 --http --http.port 4003 --http.api eth,web3,net,personal,admin,arm,dag

Then connect the nodes to each other:

# Get enode URL from validator 1
curl -s http://localhost:4001 -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"admin_nodeInfo","params":[],"id":1}' | jq -r '.result.enode'

# Add peer to validator 2
curl -s http://localhost:4002 -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"admin_addPeer","params":["ENODE_URL"],"id":1}'

Non-Validator Node

To run a non-validator node (sync only) in a fakenet:

./build/armnode --fakenet 0/3 --port 3000 --http --http.port 4000

Use 0 as the validator ID to run as a non-validator.

Using the Demo Scripts

The demo/ directory contains convenience scripts for running a multi-node fakenet:

cd armchain-client/demo

# Start a 3-validator network
./start.sh

# Stop all nodes
./stop.sh

# Clean chain data (reset everything)
./clean.sh

Demo Configuration

The demo scripts use these port assignments:

Validator	P2P Port	HTTP RPC Port	WebSocket Port
Validator 1	3001	4001	4501
Validator 2	3002	4002	4502
Validator 3	3003	4003	4503

Fakenet Parameters

Fakenet uses relaxed parameters for fast development:

Parameter	Fakenet	Devnet
Empty Block Skip	3 seconds	1 minute
Max Epoch Duration	10 minutes	4 hours
Max Epoch Gas	300,000,000	1,500,000,000
Gas Power Allocation	1000× base	1× base
Validator Password	"fakepassword"	User-defined
Hard Forks	London + LLR	London + LLR

Working with Fakenet Accounts

Pre-funded Validator Accounts

Each fakenet validator is pre-funded with 1 billion ARM (1e27 wei). Access them via the console:

# Attach to the node
./build/armnode --datadir /path/to/datadir attach

# In the console:
> eth.accounts
["0xVALIDATOR_ADDRESS"]

> eth.getBalance(eth.accounts[0])
1e+27

# Unlock account for sending transactions
> personal.unlockAccount(eth.accounts[0], "fakepassword")
true

Creating Test Accounts

# Via console
> personal.newAccount("testpassword")
"0xNEW_ACCOUNT_ADDRESS"

# Via RPC
curl -X POST http://localhost:4000 \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"personal_newAccount","params":["testpassword"],"id":1}'

Sending Test Transactions

# Via console
> eth.sendTransaction({
    from: eth.accounts[0],
    to: "0xRECIPIENT",
    value: web3.toWei(100, "ether")
  })

# Via RPC
curl -X POST http://localhost:4000 \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc":"2.0",
    "method":"eth_sendTransaction",
    "params":[{
      "from": "0xVALIDATOR_ADDRESS",
      "to": "0xRECIPIENT",
      "value": "0x56BC75E2D63100000"
    }],
    "id":1
  }'

Deploying Contracts to Fakenet

With Hardhat

// hardhat.config.js
module.exports = {
  solidity: "0.8.24",
  networks: {
    "armchain-local": {
      url: "http://localhost:4000",
      chainId: 55,
      accounts: [process.env.PRIVATE_KEY],
    },
  },
};

npx hardhat run scripts/deploy.js --network armchain-local

With the Armchain Ethers SDK

import { JsonRpcProvider, Wallet, parseEther } from "@armchain-ethersv6/ethers";

const provider = new JsonRpcProvider("http://localhost:4000");
const wallet = new Wallet(FAKENET_PRIVATE_KEY, provider);

// Deploy a contract
const factory = new ContractFactory(abi, bytecode, wallet);
const contract = await factory.deploy();
await contract.waitForDeployment();

console.log("Deployed at:", await contract.getAddress());

Resetting Fakenet

To start fresh:

# Stop the node (Ctrl+C)

# Delete chain data
rm -rf ~/.armnode/  # or your custom --datadir

# Restart
./build/armnode --fakenet 1/1 --http --http.port 4000 ...

Or if using the demo scripts:

cd demo/
./stop.sh
./clean.sh
./start.sh

Common Use Cases

Use Case	Configuration
Quick contract testing	Single validator: --fakenet 1/1
Consensus testing	Multi-validator: --fakenet 1/3, 2/3, 3/3
Frontend development	Single validator with CORS: --http.corsdomain "*"
API testing	Enable all APIs: --http.api eth,web3,net,personal,txpool,arm,dag,debug,admin
Load testing	Increase gas power, multiple validators

Limitations

• Not for production: Keys are deterministic and publicly known

• No persistence guarantees: Chain data may be lost between restarts if not backed up

• Network isolation: Fakenet nodes can only connect to other fakenet nodes with the same validator count

• No real staking: Validators are auto-registered with equal stakes

Further Reading

• Quickstart: Deploy contracts to fakenet

• Network Configuration: All network details