Overview of the ten winning projects from the ETHGlobal Buenos Aires Hackathon

Author: ETHGlobal

Compiled by: Felix, PANews

The ETHGlobal Buenos Aires hackathon concluded on November 23. This hackathon brought together top talents and experts from the Ethereum ecosystem, attracting numerous developer teams to explore new application scenarios for blockchain technology. The prize pool for this event reached 500,000 USD.

After review, ten projects stood out among the 475 entries, covering areas such as NFT, DeFi, and prediction markets. PANews takes you through a quick overview of these 10 projects.

Paybot

Paybot showcases the X402 Payment Required protocol based on blockchain micropayments, used to control access to physical devices. This system was developed specifically for the Coinbase developer platform hackathon and demonstrates transactions without Gas fees, allowing users to pay for renting robots using QUSD stablecoin without having to hold ETH for Gas fees.

The system implements a complete payment service architecture: users sign the QUSD payment authorization in their wallets, and service providers submit the transactions on-chain and pay the Gas fees. This project enables IoT and robotic applications to truly achieve micropayments; otherwise, the high Gas fees would be unbearable.

This project is built by @sprpstsn.

JetLagged

JetLagged is a decentralized prediction market platform built on Celo and Oasis, where users can predict flight delays and cancellations. The platform is built using Next.js, Bun.js, and Solidity, and is deployed on the Celo blockchain.

• Live Flight Market: Use real-time odds to predict actual flights.
• Real-time pricing: Pricing mechanism based on AMM, automatically updated according to market demand.
• Decentralized Analysis: Automatically verify flight status through Oasis backend oracle.
• Farcaster Integration: Supports Farcaster Frame mini-program.
• Celo Blockchain: Fast and low-cost transactions on the Celo network.

The project is built by Faezeh, TheMonkeyCoder, and zkfriendly.eth.

Hubble Trading Arena

Hubble Trading Arena is a fully open-source autonomous trading environment, where on-chain agents are employed, paid, and coordinated through the x402 and ERC-8004 protocols, and operate real-time reasoning and actual trading. It showcases the complete on-chain collaboration loop required for thousands of professional financial agents to work together without human intervention.

The project is built by Amy@MeetHubble.

Payload Exchange

Payload Exchange allows merchants to accept any form of payment using the x402 proxy, where the sender can choose the token, and the receiver can seamlessly obtain stable assets.

Payload Exchange is a proxy layer that intercepts x402 payment requests and introduces third parties: sponsors. This enhances the payment experience for end users, allowing them to choose alternative payment methods in addition to stablecoins or other currencies. Sponsors will pay part or all of the amount in exchange for user actions or data.

The tripartite cooperation model benefits all parties involved:

• Sponsors: Acquire users, collect data, or guide specific behaviors by paying for content access fees.
• Content providers: Lower access barriers. Monetize content without setting up paywalls.
• Users: Obtain premium content/tools for free or at a discounted price through trading operations/data instead of money.

The project is built by qap, luis, Marcelo, and Soko.

Yoga

The Yoga project has implemented a non-fungible (NF) position manager, allowing LPs to manage complex multi-range positions within a single NFT. Unlike traditional position managers where each NFT only represents a single price range, Yoga can manage multiple sub-positions (different price ranges) under a single ERC721 token, enabling complex liquidity allocation strategies across price ranges.

The contract provides a simple application binary interface (ABI), allowing LPs to easily specify the modifications they want to apply (liquidity increment), and the contract will automatically calculate how to modify the underlying UniV4 position.

The project was built by Charlie Mack, Duncan Townsend, Luigi, and Michael Fautch.

LensMint Web3 Camera

LensMint Web3 Camera is a hardware-based system that allows users to sign photos while capturing them, generating on-chain NFTs verified by zero-knowledge proof, thereby achieving tamper-proof and authenticated memories.

LensMint is a complete hardware-to-blockchain camera system designed to ensure the authenticity and ownership of real-world photographs. The system is based on a Raspberry Pi camera and employs hardware-level encrypted identities. Each photo is signed and hashed at the time of capture, verified for authenticity through zero-knowledge proofs generated by vlayer, and validated on-chain via RISC Zero. The system uploads all media to Filecoin for permanent decentralized storage and mints an ERC-1155 NFT representing certified memories. The built-in QR code system allows individuals in the photos to instantly claim their NFTs, enabling proof of attendance, certified memories, and automatic revenue sharing.

LensMint provides a trustless way to prove the device provenance, timestamp, and integrity of photos, thereby addressing issues of authenticity, provenance, and monetization for creators, journalists, event organizers, and scientific literature.

The project was built by Mohit Bhat.

Halo

Halo is a mini-program based on World Chain that converts real shopping receipts into on-chain rewards for verified users. Users scan shopping receipts from any store, and Halo evaluates them through a lightweight processing flow, then distributes rewards to users verified by World ID. Throughout the process, the user's personal identity remains private.

Shopping receipts contain important information about real economic activities, but this information is often lost or locked in closed systems. Halo captures this information, processing each receipt to extract details such as the merchant, timestamp, total amount, currency, and category. Rewards can only be claimed by specific users, thus creating a way to prevent witch attacks and protect privacy, linking offline activities with on-chain rewards.

The project is built by hellocrypto and @DNC_Labs.

zkx402 (ProofofLeak)

zkx402 is an extension of the x402 protocol that integrates zero-knowledge proofs for verifying variable payments and verifiable content.

Consumers (human or AI agents) have different pricing tiers, and users who can verify their identity using zero-knowledge proofs are eligible for discounts. Producers can prove the provenance of their content through additional zero-knowledge proofs. For example, the identity of an author confirmed by a specific journalist, proof of human authorship, and IoT data with GPS/sensor details.

Whistleblowers can receive rewards without disclosing their identity. Journalists can achieve lower access costs by proving they are human or are employed by reputable media organizations. AI agents controlled by journalists autonomously pay via x402 on Base to access private sensitive data.

The project was built by Guilherme, Lam, Ra's Al Ghul, Mark Ballew, and vaughn.

Aqua0

Aqua0 is a cross-chain shared liquidity mini-program that utilizes Aqua AMM and LayerZero messaging to achieve seamless asset transfer.

Aqua is a shared liquidity layer developed by 1inch, designed to address the inefficiencies present in current AMMs. These issues include: 1) 90% of AMM liquidity is never utilized, leading to stagnant liquidity. 2) This causes liquidity to be fragmented, as AMMs ultimately end up with idle and unutilized liquidity at different LPs across various protocols and chains.

Aqua0 improves Aqua through a cross-chain approach. The current issue with Aqua is that it can only be used on one chain at a time as an accounting layer. Aqua0 will create a cross-chain AMM market, utilizing Layer Zero's cross-chain components and Aqua's shared liquidity contracts, allowing LPs to unlock new revenue opportunities and enhance capital efficiency.

The project was built by Yudhishthra Sugumaran, Andrei De Stefani, and @tomasmazzi.

BMCP

BMCP (Bitcoin Multi-Chain Protocol) connects Bitcoin and EVM chains through true cross-chain programmability. Users can use native Schnorr signatures (Taproot/BIP340) to sign Bitcoin transactions to trigger EVM transactions (DeFi swaps, token transfers, contract calls).

Cross-chain Relay Engine (CRE) scans Bitcoin blocks and performs secure off-chain (risk management, validation) and on-chain (contract invocation) calls on chains such as Polygon and Ethereum upon detecting a valid, Schnorr authenticated BMCP message embedded in OP_RETURN, seamlessly leveraging Chainlink CCIP. BMCP ensures that all processes remain trust-minimized, anchored to the finality of Bitcoin through cryptographic techniques, and can be combined across different ecosystems.

The project was built by Vibhav Sharma, Vollantre, James Scaur, and Manuel.

Reading: AI, cross-chain, and privacy stand out, a quick look at the 10 new projects shortlisted for the ETHGlobal Cannes Hackathon.