Union is the hyper-efficient zero-knowledge infrastructure layer for general message passing, asset transfers, NFTs, and DeFi. It’s based on Consensus Verification and has no dependencies on trusted third parties, oracles, multi-signatures, or MPC. It implements IBC for compatibility with Cosmos chains and connects to EVM chains like Ethereum, Berachain (beacon-kit), Arbitrum, and more.

The upgradability of contracts on other chains, connections, token configurations, and evolution of the protocol will all be controlled by decentralized governance, aligning the priorities of Union with its users, validators, and operators.

Components

Component	Description	Language(s)
uniond	The Union node implementation, using CometBLS	Go
galoisd	The zero-knowledge prover implementation	Go Gnark
voyager	Modular hyper-performant cross-ecosystem relayer	Rust
hubble	Multi-ecosystem, GMP-enabled chain indexer	Rust
cosmwasm	CosmWasm smart contract stack	Rust
light-clients	Light Clients for various ecosystems	Rust
unionvisor	Node supervisor intended for production usage	Rust
drip	Faucet for Cosmos chains: app.union.build/faucet	Rust
evm	EVM smart contract stack	Solidity
app	app.union.build	TypeScript Svelte
site	union.build	TypeScript Astro

Quickstart

Install Nix to reproducibly build any component, and to enter a dev shell with all dependencies:

curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install

(Note that some components can only be built on Linux. If you are using macOS, we recommend using OrbStack to easily set up a NixOS VM within two minutes. Most Union developers use macOS with OrbStack, and there is no need to install Nix inside of the NixOS VM.)

You can now reproducibly build any of Union's components from source:

nix build .#uniond -L
nix build .#voyager -L
nix build .#app -L

# to see all packages, run:
nix flake show

The result of whatever you build will be in result/

You can now also enter our dev shell, which has all of the dependencies (cargo, rustc, node, go, etc.) you need to work on any component: (Don't worry, this will not affect your system outside of this repo)

nix develop

Run the following to format the entire repo and check your spelling before each PR:

nix run .#pre-commit -L

Check the #developers channel on Union's discord if you need any help with this.

Docs

The official docs are hosted here. Each individual component also has accompanying developer documentation for contributors, which you can find in each README.md.