Snowbridge

Snowbridge is a trustless bridge between Polkadot and Ethereum. For documentation, visit https://docs.snowbridge.network.

Components

The Snowbridge project lives in two repositories:

• Snowfork/polkadot-sdk: The Snowbridge parachain and pallets live in a fork of the polkadot-sdk. Changes are eventually contributed back to paritytech/polkadot-sdk
• Snowfork/snowbridge: The rest of the Snowbridge components, like contracts, off-chain relayer, end-to-end tests and test-net setup code.

Parachain

Polkadot parachain and our pallets. See https://github.com/Snowfork/polkadot-sdk.

Contracts

Ethereum contracts and unit tests. See contracts/README.md

Relayer

Off-chain relayer services for relaying messages between Polkadot and Ethereum. See relayer/README.md

Local Testnet

Scripts to provision a local testnet, running the above services to bridge between local deployments of Polkadot and Ethereum. See web/packages/test/README.md.

Smoke Tests

Integration tests for our local testnet. See smoketest/README.md.

Development

We use the Nix package manager to provide a reproducible and maintainable developer environment.

After installing Nix, enable flakes:

mkdir -p ~/.config/nix
echo 'experimental-features = nix-command flakes' >> ~/.config/nix/nix.conf

Then activate a developer shell in the root of our repo, where flake.nix is located:

nix develop

Also make sure to run this initialization script once:

scripts/init.sh

Support for code editors

To ensure your code editor (such as VS Code) can execute tools in the nix shell, startup your editor within the interactive shell.

Example for VS Code:

nix develop
code .

Custom shells

The developer shell is bash by default. To preserve your existing shell:

nix develop --command $SHELL

Automatic developer shells

To automatically enter the developer shell whenever you open the project, install direnv and use the template .envrc:

cp .envrc.example .envrc
direnv allow

Upgrading the Rust toolchain

Sometimes we would like to upgrade rust toolchain. First update polkadot-sdk/rust-toolchain.toml as required and then update flake.lock running

nix flake lock --update-input rust-overlay

Troubleshooting

Check the contents of all .envrc files.

Remove untracked files:

git clean -idx

Ensure that the current Rust toolchain is the one selected in scripts/init.sh.

Ensure submodules are up-to-date:

git submodule update

Check untracked files & directories:

git clean -ndx | awk '{print $3}'

After removing node_modules directories (eg. with git clean above), clear the pnpm cache:

pnpm store prune

Check Nix config in ~/.config/nix/nix.conf.

Run a pure developer shell (note that this removes access to your local tools):

nix develop -i --pure-eval

Security

The security policy and procedures can be found in SECURITY.md.