Build

Developers and node operators

Build BitcoinII Core, run a node safely, and use the explorer API.

Source code

Most of BitcoinII Core is MIT-licensed. The ShockWave difficulty code in src/pow.cpp is published on GitHub for review under its own proprietary source-review license, not MIT. Read the file header before reusing it.

Build from source

BitcoinII Core uses CMake, like current Bitcoin Core. On Linux, after installing the dependencies listed in doc/build-unix.md:

git clone https://github.com/Bitcoin-II/BitcoinII-Core.git
cd BitcoinII-Core
git checkout v31.1.0
cmake -B build
cmake --build build -j 4

macOS and Windows instructions are in the doc folder.

Release history

BitcoinII Core releases
Version	Date	Status
v31.1.0	Aug 29, 2026	Current. ShockWave difficulty, data limits and replay protection from block 57,750; fork-aware header sync.
v29.1.0	Nov 27, 2025	Deprecated. Pre-ShockWave: do not run on mainnet.

Ports, data folder and config file

Default ports
Network	P2P port	RPC port
Mainnet	`8338`	`8337`
Testnet4	`48338`	`48337`
Signet	`38338`	`38337`
Regtest	`18448`	`18447`

These differ from Bitcoin’s ports, so BitcoinII and Bitcoin nodes can run on the same machine.

Linux data folder: ~/.bitcoinII/
macOS data folder: ~/Library/Application Support/BitcoinII/
Windows data folder: %LOCALAPPDATA%\BitcoinII\ (older installs may use %APPDATA%\BitcoinII\)
Config file: bitcoinII.conf in the data folder
Programs: bitcoinII-qt (desktop app), bitcoinII-d (daemon), bitcoinII-cli (command line)

RPC safety

Never expose the RPC port to the internet. Anyone who can reach it with valid credentials can control the node and, with a loaded wallet, spend your coins.

Keep RPC bound to localhost (the default). Don’t add rpcbind=0.0.0.0 or a wide rpcallowip.
Don’t forward port 8337 on your router or open it in a firewall.
Prefer cookie authentication (the default) over a fixed RPC username and password. If you must use one, generate it with share/rpcauth/rpcauth.py, and never paste it into chats, issues or screenshots.
For remote access, use an SSH tunnel or a VPN.
Port 8338 (P2P) is safe to open if you want to accept incoming connections and help the network.

Solo mining with your own node

A fully synced node can serve block templates through the getblocktemplate RPC. Point solo-mining software or a self-hosted stratum server at it, set a payout address you control, and keep RPC local as described above. Most home miners will find a pool simpler.

Explorer API

The explorer is mempool-based and offers a public REST API. Examples:

# Current block height
curl https://explorer.bitcoin-ii.org/api/blocks/tip/height

# Hash of the genesis block
curl https://explorer.bitcoin-ii.org/api/block-height/0

# Latest blocks (JSON)
curl https://explorer.bitcoin-ii.org/api/v1/blocks

# Hashrate and difficulty, last 3 days (JSON)
curl https://explorer.bitcoin-ii.org/api/v1/mining/hashrate/3d

Please be gentle with request rates. The same API is also served at https://bc2mempool.com/api/.

Next: Stay safe →