Historical Momemt! Darwinia is about to open the “Golden Gate Bridge” from Ethereum to Polkadot

5 min readNov 6, 2020


Technological innovation

There are many cross-chain schemes, but the real challenge is the connection between heterogeneous chains. Currently, multisig whitelist nodes and Light Client-based bridge schemes are generally used, which are relatively safe and stable, and of which the best is Light Client-based bridge. Dawinia is developing decentralized asset endorsement technology, which is the complete realization of this Light Client-based bridge scheme, including high-performance cross-chain relay service ‘Darwinia Relay’, heterogeneous chain cross-chain transfer bridge, non-standard asset cross-chain standards and cross-chain exchange protocol, etc.

Looking back at the history of cross-chain transfer bridges, the previous open-source project is the BTCRelay developed by Consensys, which is a one-way bridge from BTC to ETH, which verifies transactions on BTC by using Ethereum smart contracts to implement BTC’s Light Client. In addition, there is the WaterLoo EOS-ETH two-way transfer bridge developed by Kyber Network, which implements the light client of the counterparty chain on ETH and EOS respectively. However, because the operating cost of smart contracts is relatively high, WaterLoo made Ethash verification compromise, not completely decentralized. Compared with smart contracts, Darwinia’s cross-chain bridge is based on the Substrate runtime, which provides more flexibility, especially in terms of gas and operating costs. It can be optimized a lot, and it can also provide better economic feasibility based on complete decentralization.

The Ethereum-Darwinia one-way bridge solves the problem of the high cost of traditional Light Client. Darwinia Relay is a universal cross-chain transfer bridge solution, mainly to solve the cost and performance problems. The traditional cross-chain transfer bridge needs to relay every block header on the opponent chain to the light client on the chain. If The block generation rate of the counterparty chain is very fast, the cost will be very high, making the solution economically infeasible and unable to be applied on a large scale. Darwinia Relay realizes the purpose of cross-chain verification while reducing costs by implementing a Super Light Client on the chain. Super Light Client uses a special MMR data structure, which has been adopted by projects such as Grin and Beam. However, in the case that the counterparty chain does not support Super Light Client, there are many things that have not been encountered in the implementation of Super Light Client on the chain. Darwinia Relay innovatively solves the challenge of implementing Super Light Client on the chain, and builds a set of economically feasible cross-chain transfer bridge solutions to provide a direction for the future cross-chain of heterogeneous chains.

Why cross-chain transfer

The assets on the mainnet can be used to participate in staking, and the current ROE is relatively high. After the genesis cross-chain stage, there is no way to transfer more assets to the mainnet. But it can now be done with the Ethereum-Darwinia one-way bridge. The users who hold Gringotts deposit receipt or Ethereum erc20 ring and kton can transfer their assets to the mainnet through the Ethereum-Darwinia one-way bridge. After reaching the mainnet, you can participate in staking to get rewards.

Let’s use the tools provided by Darwinia to make an Ethereum-Darwinia one-way bridge cross-chain transfer.

How to Cross-chain Transfer

  • Then click the “Cross-chain Transfer” button under “Darwinia” to enter the cross-chain transfer page, select “Ethereum -> Darwinia Mainnet” in the drop-down box, and then click “Cross-chain Swap”. At this time, a Metamask window will pop up to prompt you to connect to Metamask and select your ethereum address containing darwinia assets (make sure there is enough ETH to pay the network gas fee), click “Next”, and then click “Connect”:
  • After successfully connecting to metamask,there will be a form displayed. Fill in the correct “Darwinia Network account” (address starting with 2), and select the “asset type”, and fill in the transfer “amount”, click “Approve” ( When using the cross-chain bridge for the first time, there will be a ‘Approve’ step), click “Confirm” in the pop-up Metamask window:
  • After “Approve” is completed, click the “Submit” button, and click “Confirm” in the pop-up Metamask window, the page jumps to:
  • That’s all you need to do.
  • And the next step is to wait for the transaction confirmation on Ethereum and Darwinia. Click “Cross-chain History” to view the transfer confirmation progress:
  • After the Darwinia transaction confirmed, you can click “Txhash” to open subscan to view the details of the transaction:

We can see that using the Darwinia Ethereum-Darwinia one-way bridge to do cross-chain transfer is a very simple and easy thing.




As an open cross-chain bridge protocol based on Substrate, Darwinia focuses on the construction of future Internet of Tokens. TG: http://t.me/DarwiniaNetwork