Bounty: $2,000 in $USDC to the best implementation of Chain Signatures.

API: https://github.com/near/mpc-recovery/blob/6f46b0b648f9cf62cddd4c4eeea7742dbab59124/contract/src/lib.rs#L291-L297

What are Chain Signatures?

Chain Signatures are a revolutionary new cryptographic primitive revolutionizing secure multi-party computation to jointly sign a document without revealing their individual private keys. They also allow users to store private keys to EDCSA-based chains (encrypted) on NEAR so one NEAR account can control multiple accounts on different chains (Account Aggregation). This allows developers to build multi-chain apps, sponsor gas for users, and abstract all the blockchain complexity away from the end user (Chain Abstraction).

Blockchains that support ECDSA signatures includes Bitcoin, Ethereum, BSC, Doge, Z-Cash, and more. The current API can be found here: https://github.com/near/mpc-recovery/blob/6f46b0b648f9cf62cddd4c4eeea7742dbab59124/contract/src/lib.rs#L291-L297

You can learn more about Chain Signatures here

• David Millar-Durrant from Pagoda presents Account Aggregation at NEARCon (Slides, Youtube)
• Github Discussions
• Sample request and response
• API: https://github.com/near/mpc-recovery/blob/6f46b0b648f9cf62cddd4c4eeea7742dbab59124/contract/src/lib.rs#L291-L297

Potential Applications

• On-chain Encrypted Content: MPC nodes and signatures can allow any individual to have secure communication with a smart contract by depositing a encrypted payload to that contract and then have that content be re-encrypted and sent to a third party.
• MEV Mitigation: Encrypted pools of transactions that miners can’t see before they need to be executed. It works by getting every user to send encrypted bids to the chain, then the bid closes, the chain will take the encrypted bids and decrypted them and synchronously evaluate them. This will enable private dutch auctions, more efficient trading with less front-running or slippage.
• Smart Contract Owned Domains: DNSSEC can verify that everything served from your domain is always approved by the smart contract. Transparency to ensure that the application being served from the frontend is the right one. Ability to vote on the changes to the frontend rather than just backend. Everything is versioned.
• Key Markets: Multi-chain key governance in a smart contract.