node/LLM.md

node

zood — the Zoo network node. C++20. One binary.

What this repository is

The Zoo network's identity, as a program. A node is asked which network this is, what numbers that network is, where its files live, what it binds, and whether a genesis document is this network's — and this answers those.

The answers are compiled in. A node that read its own identity from somewhere editable is a node that can be pointed at a fork by editing it.

The Zoo chain is carried by a validator set that also carries other chains, so the host a validator runs on is shared and the identity is not. This repository is the identity half. The host half is a C++ package that does not yet install, export a target, or resolve its own dependencies as packages, so nothing here depends on it: zood binds no mesh and decides no block. What it does state, it states correctly, and every claim below is a case in test/check.cpp.

Layout

src/network.h    the three networks, and nothing else about them
src/network.cpp  finding one by name
src/genesis.h    what a genesis document says about which network it is for
src/genesis.cpp  reading one, and what makes one unreadable
src/main.cpp     the flags, and what is printed
test/check.cpp   every way a node could end up on the wrong network

Each answers one question. network knows nothing about documents; genesis states no identity of its own — it is handed the network to check against.

Two numbers, not one

A validator joins a NETWORK. A transaction is signed against a CHAIN. They are different numbers, and collapsing them is how a wallet and a validator come to disagree about what they are on — visible only after something has been signed for the wrong thing.

network id    1 mainnet     2 testnet     3 devnet
chain id      200200        200201        200202

The chain ids are LP-018's canonical map for this brand. The network ids are the network whose validator set carries the chain.

Ports are 9630 (RPC) and 9631 (mesh) — what the deployed nodes bind. The data directory is ~/.zood.

What is refused

Refusal is the interesting half. Every one of these has a case in test/check.cpp.

• A network name that is not one of the three. Never a default: a default would join the wrong network on a typo and look like it had started correctly.
• A genesis whose chain is not this network's chain.
• A genesis that names a network, when that is not this network. A chain document carried inside another network's genesis belongs to that network.
• A field that is present and unreadable — a quoted chain id, a negative one. Never a zero.
• A document with no config, or a config with no chain id.
• An alloc that is not a set of accounts.
• A document that wraps itself past the nesting limit, which would otherwise recurse until the stack ends.
• --rpc and --mesh on one address.

The genesis shapes

Both shapes on disk are read, because both are what is written: the chain's own document, or a whole-network document carrying it under cChainGenesis — as an object, or as a string holding the document.

Building

cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build -j8
ctest --test-dir build --output-on-failure

Everything is built -Wall -Wextra -Wpedantic -Werror. The JSON reader is one FetchContent_Declare with FIND_PACKAGE_ARGS, so the installed package is used when the host has it and fetched at the pinned tag when it does not — one declaration, the same build either way.

Conventions

• Copyright is Zoo Labs Foundation; new files carry SPDX-License-Identifier: BSD-3-Clause-Eco. Third-party attribution lives in NOTICE.
• Another network's brand does not appear in prose, help text, log lines, or anything a person reads.
• LLM.md is the one document file. CLAUDE.md, AGENTS.md and GEMINI.md are gitignored symlinks to it.