Installing Fukuii

Install Fukuii, then start a node on the network you want. The same binary runs every network it supports, so nothing below changes except one argument.

docker run ghcr.io/fukuii-project/fukuii-cli

Documentation

Scala 3PekkoJVMRocksDB

Install and run

Two steps: get the binary onto the machine, then tell it which network to join. The network is a single argument, and the ones below are configured and ready. Testnets take the same commands with a different argument.

What you get is a full node: it validates every block against the protocol rules rather than trusting a peer, serves JSON-RPC locally, and keeps its own copy of state. The first sync takes hours to days depending on the network and the disk, and the node is usable for reads well before it reaches the tip.

Layer 1: Install

Get the binary onto your machine. Native installs require JDK 25 LTS, from your distribution's OpenJDK package or from Eclipse Temurin. The Docker image bundles everything.

# 1. Install the current JDK LTS (25)
sudo apt update && sudo apt install -y openjdk-25-jdk    # Debian, Ubuntu
# sudo dnf install java-25-openjdk-devel                 # Fedora, RHEL
java -version

# 2. Download and extract the Linux distribution
curl -LO https://github.com/fukuii-project/fukuii-cli/releases/latest/download/fukuii-<ver>-linux.tar.gz
tar -xzf fukuii-<ver>-linux.tar.gz

# 3. Put the launcher on PATH, then verify
export PATH="$PWD/fukuii-<ver>/bin:$PATH"
fukuii --version

# 1. Install the current JDK LTS (25)
#    Download the macOS .pkg for your architecture from adoptium.net
#    and run it, then confirm it is on PATH:
java -version

# 2. Download and extract the macOS distribution
curl -LO https://github.com/fukuii-project/fukuii-cli/releases/latest/download/fukuii-<ver>-macos.tar.gz
tar -xzf fukuii-<ver>-macos.tar.gz

# 3. Put the launcher on PATH, then verify
export PATH="$PWD/fukuii-<ver>/bin:$PATH"
fukuii --version

# 1. Install the current JDK LTS (25)
#    Download the Windows .msi from adoptium.net and run it,
#    then confirm it is on PATH:
java -version

# 2. Download and extract the Windows distribution
Invoke-WebRequest `
  -Uri "https://github.com/fukuii-project/fukuii-cli/releases/latest/download/fukuii-<ver>-windows.zip" `
  -OutFile fukuii.zip
Expand-Archive fukuii.zip -DestinationPath .

# 3. Put the launcher on PATH, then verify
$env:Path += ";$PWD\fukuii-<ver>\bin"
fukuii --version

# No JDK required, the image bundles everything
docker pull ghcr.io/fukuii-project/fukuii-cli:latest

# Verify
docker run ghcr.io/fukuii-project/fukuii-cli:latest --version

Build from source (advanced, requires Scala toolchain)

# Requires the current JDK LTS (25) and sbt, the Scala build tool
git clone https://github.com/fukuii-project/fukuii-cli
cd fukuii && sbt assembly
# Output: target/fukuii-assembly-<ver>.jar

Layer 2: Run a node

Once installed, the network is a single argument. The two production networks are below; their testnets take the same commands with a different argument.

Proof-of-Work / ETChash

Ethereum Classic

PoW

Runs standalone. Proof-of-Work needs no consensus layer, so this is the whole deployment.

docker run ghcr.io/fukuii-project/fukuii-cli --network=etc

Ethereum Classicetcchain 61
Mordormordorchain 63

Proof-of-Stake / Engine API

Ethereum

PoS

Needs a consensus layer. Fukuii can run one in the same process, or be driven by an external consensus client over the Engine API.

docker run ghcr.io/fukuii-project/fukuii-cli --network=eth

Ethereum Mainnetethchain 1
Sepoliasepoliachain 11155111

The complete form, with persistent storage and, for Proof-of-Stake, the Engine API:

# Native
fukuii --network=<network>

# Docker
docker run -v fukuii-data:/var/lib/fukuii \
  ghcr.io/fukuii-project/fukuii-cli:latest --network=<network>

# Consensus layer in the same process
fukuii --network=eth \
  --consensus-layer-enabled \
  --fee-recipient=0xYourAddress

# Or drive it with an external consensus client, sharing one
# JWT secret over the Engine API on localhost
openssl rand -hex 32 | tr -d "\n" > jwt.hex
fukuii --network=eth \
  --engine-rpc-enabled \
  --engine-rpc-port=8551 \
  --engine-jwt-secret=./jwt.hex

Fukuii pairs with Lighthouse, Prysm, Teku, Lodestar and Nimbus. Point your consensus client at http://localhost:8551 using the same JWT file.

Supported networks and their launch arguments
Network	Argument	Consensus	Chain ID
Ethereum Classic	etc	PoW	61
Mordor	mordor	PoW testnet	63
Ethereum Mainnet	eth	PoS	1
Sepolia	sepolia	PoS testnet	11155111

Next steps

A syncing full node is the default. These add a role on top of it. Mining applies to Proof-of-Work networks; validating applies to Proof-of-Stake networks.

Stake (PoS)

Fukuii ships the consensus layer, or pair an external one over the Engine API.

Mine (PoW)

Configure a coinbase address and connect a miner. Applies to every configured Proof-of-Work network.

Archive node

Full history retained, which multiplies the disk requirement.

Run as a service

Keep the node running under systemd (Linux), launchd (macOS), or a Windows Service.

Before you start

What a node needs, and what determines each requirement
What	Requirement	What drives it
Java	Current JDK LTS (25)	Any OpenJDK build of the current LTS. The Docker image bundles one.
Memory	8 GB minimum for the JVM heap	Add headroom for each additional network run in the same process.
Disk space	Set by the network and the storage approach	A pruned Ethereum mainnet node is on the order of a terabyte and grows with the chain. Ethereum Classic is substantially smaller. An archive node is a multiple of the pruned figure on either.
Disk type	SSD, and NVMe for a validator, mining pool or public RPC node	State access during sync is random rather than sequential, which a spinning disk cannot keep up with.
CPU	Highest while syncing, lower at the chain tip	Size for the sync, then scale down on observed usage rather than on the peak.