Keep it Confidential: Sapphire Hackathon Winners

Oasis Network
Oasis Foundation


With Sapphire — the industry-first confidential EVM ParaTime — recently coming to testnet, we wanted teams to try their hand at building the first-ever confidential dApp in Solidity.

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The Keep it Confidential hackathon offered developers the chance to experience confidential smart contracts in a language they already know and understand. We have received quite a few great applications of how Sapphire can be used to change the face of blockchain and offer confidentiality to EVM-based dApps.

Congratulations to the teams below who made it to the Top 3!

1st Place: ARX Protocol

ARX is a P2P platform for on- and off-ramping fiat. The user makes the bank transfer (or whichever payment method the two deal parties have agreed upon), and then it is up to the counterparty to verify and confirm that the funds have been received. Once confirmed by the counterparty, the crypto funds locked in the escrow smart contract are released. The collateral both parties had to lock before initiating the trade is also unlocked at this stage.

ARX does not verify the progress of the trade, nor does it take custody of the funds at any point. Based on math and game theory, the collateral system has been designed as the core mechanism for dispute resolution and fraud prevention.

To see a demonstration of ARX, please see the video: ARX Protocol

2nd Place: Momentum

Momentum is an on-chain and fully confidential messaging service projected for mass adoption. Momentum allows for the sending and receiving messages to and from wallet addresses in a confidential nature. Through Sapphire, these messages remain encrypted until they are unlocked through Momentum.

To see a demonstration of Momentum, please see the video: Momentum dapp — Application for the Sapphire Hackathon

3rd Place: Onchain-ID

The On-Chain.ID platform is about storing personal data on-chain with the option to grant access to third-party providers safely and without intermediaries.

Users can add/remove data they want to expose to third-party providers. Providers can then query the data quickly and effectively to gain access to the allowed information.

The whole system works on-chain and is fully decentralized with total transparency for users and providers. This is possible because of the confidential nature of the Sapphire ParaTime.

To see a demonstration of ON-chain.ID, please see the video: Onchain-ID

We look forward to more teams and developers exploring and building on Sapphire. The ability to use Solidity, while also adding on-chain confidentiality, has the potential to hugely impact the blockchain world and bring it forward into Web3.



Oasis Network
Oasis Foundation

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