As part of our ongoing efforts to keep the community informed about our progress with Snowbridge, we’d like to share an update on what our team has accomplished over the past month.
Workshop with Parity XCM/Bridges team
Our team recently joined the Parity bridges and XCM team for an intensive three-day brainstorming workshop. The primary focus was to explore the viability of an unordered message delivery design for Snowbridge, ensuring the upcoming XCM v5 supports all future use cases for Snowbridge and to design how Snowbridge will be enabled on Kusama.
Unordered Message Delivery
Currently, Snowbridge requires ordered message delivery, where each message sent over Snowbridge has a nonce, and messages must be processed in sequence. This design was initially chosen due to its simpler implementation and deterministic execution guarantees.
The team is implementing new message delivery architecture that removes the requirement for ordered message delivery. This change eliminates much of the off-chain fee calculation complexity, allows flexibility around fee assets used and allows relayers to choose messages that are profitable to relay.
Advantages of the new design include:
- Lower transaction fees, since fees can be calculated off-chain and topped up on-chain if too low.
- Support for arbitrary contract execution on both Ethereum and Polkadot using the
Transactfunctionality. - Greater flexibility in bridging usage, such as bundling multiple assets in a single transfer or combining
Transactmessages with asset transfers.
The full design of this change is available online. Community input is encouraged and welcome!
Snowbridge on Kusama
There has been ongoing discussion around deploying Snowbridge on Kusama. After deliberation with the Parity team, we’ve decided that Snowbridge will be available on Kusama, but through a composition of the Polkadot-Kusama bridge.
The new architecture will enable double-bridging use cases and broader interoperability within the Polkadot ecosystem.
Merge of Polkadot-native assets on Ethereum feature
The Polkadot native assets feature has been completed and merged into the Polkadot SDK September release. The feature will undergo a security audit by Oak Security in October, with an expected release on the Polkadot mainnet around December. We anticipate this feature will encourage more parachains to integrate with Snowbridge. Polar path implementations will migrate to the Snowbridge official implementation.
Free Consensus Updates from Ethereum
In August, we upgraded the Snowbridge Ethereum client, reducing monthly running costs from approximately $17,000 to around $1,700. Inspired by the Polkadot-Kusama bridge, we implemented a feature to allow certain valid updates to the Ethereum client to be free. If the update is valid and recent, it will incur no cost. This change, along with the Polkadot native assets feature, will be audited to ensure robustness and prevent exploitation.
Preparing for the Ethereum Electra Upgrade
Ethereum is planning a network upgrade, Electra, for early 2025. Since this upgrade affects consensus data structures used by the Ethereum client, we have made the necessary code changes and will begin testing once the Ethereum clients release a stable version for Electra.
Snowbridge on Paseo & Westend
With Rococo being sunset in early October, we have been focusing on ensuring Snowbridge is supported on stable testnets. Snowbridge is now live and ready for testing on both Westend and Paseo. We have also improved our operational processes to ensure these testnets are always available and usable.
Lowering Transaction Fees
We submitted an OpenGov proposal to update the bridge pricing parameters, which successfully lowered the transfer fees. The new fees are:
- Ethereum → Polkadot: $0.75
- Polkadot → Ethereum: 6.127801 DOT
We are aware of concerns regarding the high transaction fees from Polkadot to Ethereum, primarily driven by Ethereum gas prices. The new unordered message delivery architecture will significantly reduce these fees.
State of Integrations
Our team has been working to integrate Snowbridge into wallets and dApps, where its true potential can be realized. Integration work often spans several months due to varying team release cycles and priorities.
Turtle by Velocity Labs
Turtle, a UI built specifically for Snowbridge by Velocity Labs, is production-ready for Ethereum to Polkadot AssetHub transfers. The next release will support transfers from Ethereum to other parachains (Hydration, Moonbeam, Bifrost) and back. Turtle is available to use at app.turtle.cool.
SubWallet & Talisman
Assets bridged with Snowbridge are now visible in the latest version of both SubWallet and Talisman, making it easier for users to track their assets. Weth from Ethereum can be bridged to Polkadot AssetHub using SubWallet.
Hydration & Moonbeam
ERC-20 assets can now be bridged over to Hydration and Moonbeam. However, sending ERC-20s back to Ethereum from these parachains still requires configuration and deployment, along with UI updates to display these assets.
Bifrost
Bifrost fully supports ERC-20 transfers back and forth. The only remaining task is to reflect the asset status in the UI.
Summary
Snowbridge has been live since June and remains the only trustless bridge between Ethereum and Polkadot. Our ongoing development efforts aim to make Snowbridge a versatile, cost-effective, and reliable bridge solution for the Polkadot and Ethereum ecosystems.