Written by AIMan@黄金财经
The ETHGlobal New York 2025 Hackathon was held in New York from August 15th to 17th, 2025. A total of 275 projects were selected during the 36-hour hackathon.
On August 18th, ETHGlobal New York announced the 10 winning projects: Swap Pay, Pumpkin Spice latte, Noah, Hardhat3-Ledger, Kyma Pay, x402-flash, Primer, TX Delay Insurance, and Rivals.
Below are brief introductions to the 10 winning projects:
Swap Pay
Swap Pay is an SDK that simplifies Web3 payments. Swap Pay leverages Chainlink data streams, allowing users to view real-time prices for all tokens in their wallets. This provides a comprehensive understanding of the value of their balances. At checkout, users simply select the contribution amount for each token to pay in PYUSD. Using EIP-5792, users can execute a single transaction without having to go through multiple exchanges, approvals, and trades.
Demo link: https://swappay.netlify.app/
Pumpkin Spice Latte
Pumpkin Spice Lattes is a bonus-linked savings app that turns the tedium of DeFi earnings into exciting jackpots. Users deposit stablecoins into a shared pool. The principal remains safe, but the pool's earnings are used for regular prize draws. Winners receive a generous "latte bonus," while those who don't win keep their deposits. It's a fun and easy-to-get-started way to make saving engaging while introducing user-friendly DeFi mechanisms.
Demo address: https://pumpkin-spice-latte.netlify.app/
Noah
Noah is a cryptocurrency inheritance and security system that connects digital assets with real-world verification for ultimate security. Noah ensures that no matter what happens to the user or the user's key, their crypto assets will not be lost.
Noah utilizes a deadlock switch and a neutrally incentivized MEV mechanism (to ensure maintenance without Noah intervention) to ensure that if there is no owner intervention within a specified time (meaning they cannot access their wallet or themselves), the funds will always be withdrawn and liquidated to the intended beneficiary address. Demo link: https://ethnyc-2025-noah-qtx3-git-main-jtraversas-projects.vercel.app/ Hardhat3-Ledger Hardhat3-Ledger adds Ledger wallet integration to Hardhat3, enabling secure hardware transaction signing. Hardhat3-Ledger adds Ledger wallet support to Hardhat 3 via the device-management-kit library, enabling developers to seamlessly integrate Ledger hardware wallets with the latest version of Hardhat. This enables developers to integrate hardware-based secure signing for transactions, messages, and typed data when creating projects using Hardhat 3. With this integration, users can sign transactions on their Ledger wallets when deploying smart contracts to any EVM network using Hardhat 3. Source code: https://github.com/ericliujt/hardhat Kyma Pay is an on-chain financial infrastructure that makes it easy for merchants to accept GENIUS Act-compliant stablecoin payments: instant global payments at one-tenth the cost of Stripe (0.15% vs. Stripe's 1.5% stablecoin payment fee). Kyma Pay supports PYUSD, USDC, USDT, and USDe. To enable highly efficient stablecoin exchange between merchants and customers, Kyma Pay utilizes the Orbital AMM design deployed on Arbitrum One. This design uniquely applies the Uniswap V3 centralized liquidity concept to a new type of liquidity pool that supports hundreds of stablecoins, including PYUSD, UDSC, USDT, and USDe. Source code: x402-flash enables x402 micropayments with zero settlement latency overhead. x402-flash is a new approach designed to eliminate latency, bringing rich x402 expressiveness to clients. The flash architecture works by using escrow smart contracts to guarantee payment to providers while giving clients access to near-instant API responses, limited only by the amount locked in escrow. This benefits both x402 creators and end users, who can conduct large-scale microtransactions limited only by the funds in their self-custodial wallets.
Demo link: https://github.com/sleepysort/x402-flash
Primer
Primer is a Chrome extension that makes crypto payments on Amazon seamless by using gift cards as an invisible checkout layer.
Primer embeds a "Checkout with Crypto" button directly into the Amazon order page, styled using Amazon's own design system for a native experience. Upon clicking, users are connected to a wallet like Coinbase Wallet, MetaMask, or Phantom. They send USDC or other supported assets to our merchant address, and the transaction is instantly verified using Coinbase's CDP Data API. Once funds are confirmed, the Primer backend automatically purchases an Amazon gift card and applies it to the order.
Demo: https://youtu.be/j6ciQXpH00o
TX Delay Insurance
TX Delay Insurance aims to mitigate the inconvenience and financial losses caused by transaction delays in the Ethereum Virtual Machine (EVM) network. It introduces a smart contract that acts as an insurance provider, allowing users to recover losses due to delays without modifying the original transaction. The solution also uses an RPC proxy to record proof of transaction delays, enabling efficient claims processing.
Github: https://github.com/jordan-public/transaction-delay-insurance/blob/main/demo/README.md
Rivals
An AR PVP shooter where you fight zombies in the real world to earn RIVAL tokens.
Rivals is a revolutionary augmented reality (AR) multiplayer shooter. Rivals combines the immersive AR experience of apps like Pokémon GO with the competitive intensity of first-person shooters, transforming the real world into a competitive gaming arena. More than just a mobile game, it's a sophisticated fusion of Unity AR Foundation, blockchain economics, and AI-driven game mechanics to create a persistent, location-based gaming ecosystem where players compete for cryptocurrency rewards, giving real monetary value to in-game achievements.
Demo address: https://rivals.nyc/
Anais
Alex
Miyuki
Weiliang
Weatherly
Catherine