Intergalactic PioNEARing with Axelar

✨ Inspiration

This cutting-edge technology is enabled by the release of Aurora Engine 2.9.0 on April 21st 2023, which allows Near XCC cross-contract calls from within Aurora EVM. We combine this capability with the power of Axelar GMP to allow users in any EVM or Cosmos chain to make a cross-chain call to NEAR smart contracts.

👀 What it does

To showcase this technique, we developed an intergalactic themed passport dApp which allows users to gain a stamp in their passport for each chain they use along the way. Once the space traveler makes it all the way to NEAR, a celebratory social media post is created on Near Social, a smart contract on the NEAR blockchain. Overall, a smart contract on Avalanche (or any other Axelar-supported chain) makes a successful Interchain Message and Cross-Chain Call to a smart contract in the NEAR blockchain.

🌌 Example Interchain Transaction to NEAR

Using Axelar Explorer, you can see how we sent the transaction using General Message Passing: Successful Transaction on Axelar Explorer. That transaction continues on through to NEAR, which is best viewed on NEAR explorer: Successful Transaction on NEAR Explorer. As a result, the social media post requested in the body of the call on Avalanche is successfully posted to a NEAR smart contract, and the results can be viewed on the Near Social website: Successful Near Social Passport Post Creation.

💻 How we built it

We created 2 EVM smart contracts in Solidity, HomePlanet.sol and NearlyIntergalactic.sol. These contracts use Axelar General Message Passing to make a cross-chain call from the Home Planet (any chain supported by Axelar; we used Avalanche) to the Nearly Intergalactic contract in Aurora. This contract uses a version of Aurora SDK that we customized for this purpose (seen here) to make an XCC cross-contract call at the NEAR level.

For the front end, we used React-Typescript with ethers.js and MetaMask integration to create an intergalactic traveler passport dApp, showcasing the interchain functionality by awarding the user with a stamp for each chain visited along the way, and finally posting the completed passport to Near Social by successfully making a NEAR call all the way from our Home Planet of Avalanche.

🚀 Accomplishments that we're proud of

• We connected two blockchains that were never before possible to connect in this way!
• We demonstrated how to expand the capabilities of Axelar to include support for Interchain calls to NEAR.
• We created a dApp frontend which we enjoy using and which integrates multiple chains.

✅ Experience learning and using Axelar

+ The interchain capability allowed us to really bring this idea to life
+ Tutorials and docs were really well made so really helped hitting the ground running
+ AxelarScan made it really easy to visualize the GMP transactions as they went through

- When running on testnet, the time seemed to vary from 1 minute 30 to 4 minutes 30 for the same transaction
- When AxelarScan errors, it isn't too verbose on the cause of error

📈 What's next for Intergalactic PioNEARing with Axelar

We are excited to have been successful in connecting NEAR with Axelar. Some of the next steps we look forward to include:

• Interchain Tokens (ERC-20 to NEP-141)
• Interchain NFTs (ERC-721 to NEP-171)
• Arbitrary Near Cross-Contract Calls
• 2-way GMP Equivalent

Links

Powerpoint Presentation

Thank you! We hope you enjoy our multi-chain, multi technology project which opens more doors in the web3 ecosystem.

Built With

• aurora
• axelar
• near
• react
• solidity
• typescript