BEEFY (Bridge Efficiency Enabling Finality Yielder) is a secondary protocol running along GRANDPA Finality to support efficient bridging with non-Substrate blockchains, currently mainly ETH mainnet.

It can be thought of as an (optional) Bridge-specific Gadget to the GRANDPA Finality protocol. The Protocol piggybacks on many assumptions provided by GRANDPA, and is required to be built on top of it to work correctly.

🚧 BEEFY is currently under construction - a hardhat is recommended beyond this point 🚧

• Build
• Documentation
• Project Layout
• Running BEEFY

To get up and running you need both stable and nightly Rust. Rust nightly is used to build the Web Assembly (WASM) runtime for the node. You can configure the WASM support as so:

rustup install nightly
rustup target add wasm32-unknown-unknown --toolchain nightly

Once this is configured you can build and test the repo as follows:

git clone https://https://github.com/paritytech/grandpa-bridge-gadget.git
cd grandpa-bridge-gadget
cargo build --all
cargo test --all

If you need more information about setting up your development environment Substrate's Getting Started page is a good resource.

The best way to get going with BEEFY is by reading the walkthrough document! This document puts BEEFY into context and provides motivation for why this project has been started. In addition to that the current status as well as a preliminary roadmap is presented.

BEEFY brainstorming is a collection of early notes and ideas, still worth checking out.

What follows is an overview of how the project repository is laid out. The main components are the beefy-gadget which is a POC of the BEEFY round logic. beefy-pallet which is mainly a thin integration layer over the session pallet and keeps track of the current authorities. Finally the BEEFY primitives crate which contains most of the type definitions for the BEEFY protocol.

The primitives crate also contains a test light_client which demonstrates how BEEFY would be utilized by a light client implementation.

├── beefy-cli        // BEEFY utilities and testing aids
│  └── ...
├── beefy-gadget     // The BEEFY gadget
│  └── ...
├── beefy-node       // A Substrate node running the BEEFY gadget
│  └──  ...
├── beefy-pallet     // The BEEFY pallet.
│  └──  ...
├── beefy-primitives // The BEEFY primitives crate includig a test light client
│  └──  ...
├── beefy-test       // The BEEFY test support library
│  └──  ...
├── docs             // Documentation
│  └──  ...

Currently the easiest way to see BEEFY in action is to run a single dev node like so:

$ RUST_LOG=beefy=trace ./target/debug/beefy-node --tmp --dev --alice --validator

Expect additional (more useful) deployment options to be added soon.