Open House Archive
Welcome to the Open House Archive - your central repository for accessing all previous Open House buildathons and projects.
Welcome to the Open House Archive - your central repository for accessing all previous Open House buildathons and projects.
Most Hackathon Won
Most Project Built
Manobendra Mandal
Vivek Sahu
simp1e
Aaditya Rawat
Skia Variants
Akan
INSTANT WIN — The distribution layer for tokenized assets The trillion-dollar problem nobody solved Tokenized assets are coming to Arbitrum at scale. Robinhood Chain will issue them. Institutions will mint them. And then somebody has to put them in the hands of real people — millions of them, most of whom have never installed a wallet. Right now, that layer does not exist. Every distribution tool today forces a choice: verifiable but crypto-only, or accessible but unprovable. A brand giving away 10,000 tokens picks a spreadsheet and a promise. A protocol doing an airdrop reaches the same 200,000 wallets everyone else reaches. The 3 billion people outside crypto stay outside. What we built INSTANT WIN is the rail between them. A campaign holds its prize in a verified contract on Arbitrum One. Winners are drawn by Chainlink VRF — nobody picks, not even us. Prizes are claimed straight from the contract, and claims can never be blocked. Every entry, every draw, every payout is on Arbiscan. And the entrant? They use their email. No wallet, no extension, no gas, nothing to install. Under the hood each person gets a real wallet, created invisibly, signing their own on-chain entry. This is the part everyone claims and almost nobody does honestly: no relayer stuffing entries in bulk. The contract requires each entry to come from its own participant, so the proof holds. Web2 in, proof out. One verified person, one entry — phone verification, zero cost per participant, no bot farms taking the prize. Live on Arbitrum One today Not a demo. Not a testnet. Deployed, verified, running. Lottery — 30-minute rounds, VRF draws, pull-payment prizes. Automated end-to-end by Chainlink CRE. Event Center — anyone runs a campaign. Prize modules for ERC-20, ERC-721 and ERC-1155, all deployed and verified, so a campaign can distribute any tokenized asset — including real-world assets issued on Arbitrum and Robinhood Chain. Four paths, one barrier — creators and entrants each choose wallet or no wallet. Phone verification is mandatory in all four. The platform never holds a prize it cannot prove it delivered. Core: 0xEA91eb545FBB7e82f0085ff30555ed06C1Baf739 Lottery: 0xB1935f2d6D0A8dEb7cfB074b17f179fd842d324a Don't believe us. Go check. Where this goes Physical prizes as NFT vouchers — a brand uploads a product, the platform mints the voucher, the winner redeems it in-store. Creator identity signed on-chain, so a winner denied a prize holds a contract, not a screenshot. A creator score built on confirmed deliveries — the one asset in this space that capital cannot buy and only time can build. Then the regulated entity, then licensing, then any platform instrument. In that order, never before it. Why now The rails for tokenized assets are being laid this year. The distribution layer is not. We built it, it runs, and it is the only one where the person receiving the asset does not need to know what a wallet is. Stack Solidity 0.8.21 / Foundry · Chainlink VRF v2.5 · Chainlink CRE · React + wagmi/viem · Vercel serverless · Supabase · Resend Four independent security audits. 425 tests. Migrations executed against a real Postgres before touching production. The proof is in the repo — as it should be.
Cross-chain Execution Oracle — "is it safe to send NOW?" Kernel-level eBPF health signals for 12 L2 chains. x402 micropayments ($0.01/query). $0.09 on-chain revenue. M8ven Verified MCP server. 695+ tests.
Hood Relief is a community relief pool. Someone in trouble a medical bill, a stolen wallet, a lost job, a house fire files a case describing what happened and what they need. The case opens for a five-day community vote. One wallet, one vote. If it clears quorum, funds are released from the shared pool and the payout is written to a public ledger with its transaction hash. No single case can request more than a set percentage of the pool balance. There is a second path that skips all of that: a direct campaign, where the creator names their own payout address and supporters send money straight to it. Hood Relief never holds that money and never releases it. The payout address locks the moment the first donation confirms, so nobody can build an audience on one address and swap in another. The project's home chain is Robinhood Chain, an Arbitrum Orbit L2. Donations are also accepted and verified on Arbitrum One, Ethereum, Base, Optimism, Polygon, BNB Chain, Avalanche, Solana and Bitcoin every transfer is proven server-side against the chain before it counts toward the pool. Members without a wallet sign in with email or Google and get an embedded wallet, because the people this is for are usually not the people who already own a hardware wallet. It is live at hoodrelief.com.
Local-first wallet-security prototype with a working Arbitrum Sepolia policy-commitment demo. Controlled browser tests allow matching requests and block approval, recipient and policy mismatches.
x402-powered AI market intelligence for humans and autonomous agents.
On-chain sponsored banners that reward viewers in WETH for verified visibility.
AgentGuard VerifyPay is a policy-controlled escrow layer for autonomous AI agents on Arbitrum. It lets a Buyer Agent hire a Seller Agent within explicit budget, asset, risk, and expiry rules. Quotes that violate policy are BLOCKED, invalid results are FROZEN, and payment is released only after independent verification with publicly verifiable evidence.
Apraxus is blockchain infrastructure for the autonomous economy, enabling autonomous agents, programmable payments, and machine-to-machine transactions through EVM-compatible infrastructure and developer-focused onchain tooling.
A decentralized dispute resolver powered by GenLayer's AI consensus. Three AI agents (Client Lawyer, Freelancer Lawyer, Neutral Judge) analyze the evidence and reach a verdict.
SliverVine ExoMesh (Module A) — ExoMesh Agentic Guard (EIP-1193/5792/6963+) pre-consensus exoskeleton · SSRC (pkg/soil_core.wasm · src/services/risk-control.ts · sub-1.8µs warm soil check). SliverVine Sanctuary (Module B) — Sanctuary Async Escort (ERC-7540+) · Treasury escort · Robinhood / Across compliance ingress. V1.0 Buildathon Baseline: Public Open Gateway — no API key · 5 RPS (X-SliverVine-Tier: public).
Autonomous AI agent civilization on Arbitrum with Conway state engine, hybrid post-quantum security, and onchain settlements.
任意钱包地址 → 活的链上生命体：9 阶段生命周期 3D 实时可视化