A Roundup of Ten Winning Projects from the ETHGlobal Buenos Aires Hackathon

Original author: ETHGlobal

Original translation by Felix, PANews

The ETHGlobal Buenos Aires Hackathon concluded on November 23. This hackathon brought together top talent and experts from the Ethereum ecosystem, attracting numerous developer teams to explore new applications of blockchain technology. The event offered a prize pool of $500,000.

After evaluation, ten projects were selected from 475 entries, covering areas such as NFTs, DeFi, and prediction markets. PANews gives you a quick overview of these 10 projects.

Paybot

Paybot showcased its X402 Payment Required protocol, a blockchain-based micropayment protocol for controlling access to physical devices. Developed specifically for a Coinbase developer platform hackathon, the system demonstrated gas-free transactions, allowing users to pay for rented bots using the QUSD stablecoin without holding ETH for gas fees.

This system implements a complete payment service architecture: users sign QUSD payment authorization in their wallets, service providers submit the transaction on-chain and pay the gas fees. This project enables true micropayments for IoT and robotics applications, where otherwise high gas fees would be prohibitive.

This project was 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 deployed on the Celo blockchain.

• Real-time Flight Market: Predict actual flights using real-time odds.
• Real-time pricing: Based on the AMM pricing mechanism, it is automatically updated according to market demand.
• Decentralized resolution: Flight status is automatically verified through the Oasis backend oracle.
• Farcaster Integration: Supports Farcaster Frame mini-programs.
• Celo Blockchain: Conduct fast, low-cost transactions on the Celo network.

This project was 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 hired, paid, and coordinated via the x402 and ERC-8004 protocols, and run real-time inference and live trading. It demonstrates the complete on-chain collaboration loop required for thousands of professional financial agents to work together without human intervention.

This project was built by Amy@MeetHubble.

Payload Exchange

Payload Exchange allows merchants to accept any form of payment using the x402 agent. The sender can choose a token, while the receiver can seamlessly obtain stable assets.

Payload Exchange is a proxy layer that intercepts x402 payment requests and introduces a third party: the sponsor. This expands the end-user's payment experience, allowing users to choose payment methods beyond stablecoins or other currencies. The sponsor pays part or all of the amount in exchange for user actions or data.

The tripartite cooperation model benefits all participants:

• Sponsors: Acquire users, collect data, or guide specific behaviors by paying for access to content.
• Content providers: Lowering the barrier to entry. Content monetization can be achieved without setting up paywalls.
• Users: Get premium content/tools for free or at a discounted price by trading operations/data instead of money.

This project was built by qap, luis, Marcelo, and Soko.

Yoga

The Yoga project implements 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 represents only one 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) that allows LPs to simply specify the modifications (liquidity increments) they want to apply, and the contract automatically calculates how to modify the underlying UniV4 positions.

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 can sign photos while they are being taken and generate on-chain NFTs with zero-knowledge proofs, thereby achieving tamper-proof and authenticated memories.

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

LensMint provides a trustless way to prove the device origin, timestamp, and integrity of photographs, thus solving the issues of authenticity, provenance, and monetization for creators, journalists, event organizers, and scientific literature.

This project was built by Mohit Bhat.

Halo

Halo is a mini-program built on WorldChain that converts real shopping receipts into on-chain rewards for verified users. Users scan any store's receipt, Halo evaluates it through a lightweight processing flow, and then distributes the rewards to users verified with their World ID. Throughout the entire process, the user's personal identity remains private.

Shopping receipts contain crucial information about real-world economic activity, but this information is often lost or locked in closed systems. Halo captures this information, processing each receipt to extract detailed details such as the merchant, timestamp, total amount, currency, and category. Rewards can only be claimed by specific users, creating a Sybil-proof and privacy-protecting mechanism that links offline behavior to on-chain rewards.

This project was 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) are offered different pricing tiers, with discounts available to users who can verify their identity using zero-knowledge credentials. Producers can prove the source of their content by attaching zero-knowledge proofs. Examples include verified authorship by a specific journalist, proof of human creation, and IoT data with GPS/sensor details.

Whistleblowers can receive payment without revealing their identity. Journalists can obtain access at a lower cost by proving they are human or work for a reputable media organization. AI proxies 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 enables seamless asset transfers using Aqua AMM and LayerZero messaging.

Aqua is a shared liquidity layer developed by 1inch to address the inefficiencies present in current AMMs. These inefficiencies include: 1) 90% of AMM liquidity is never used, leading to liquidity stagnation. 2) This results in fragmented liquidity, as AMMs end up with idle and unused liquidity across different LPs on different protocols and chains.

Aqua0 improves upon Aqua through cross-chain functionality. Aqua's current limitation is that, as a ledger layer, it can only be used on one chain at a time. Aqua0 will create a cross-chain AMM market, leveraging Layer Zero's cross-chain components and Aqua's shared liquidity contracts to enable LPs to unlock new yield opportunities, thereby improving capital efficiency.

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

BMCP

BMCP (Bitcoin Multi-Chain Protocol) connects the 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).

The Cross-Chain Relay Engine (CRE) scans Bitcoin blocks and, upon detecting a valid, Schnorr-certified BMCP message embedded in OP_RETURN, executes secure off-chain (risk management, verification) and on-chain (contract calls) calls on chains such as Polygon and Ethereum, seamlessly leveraging Chainlink CCIP. BMCP ensures all processes remain trust-minimized, is cryptographically anchored to Bitcoin's finality, and can be combined across different ecosystems.

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