Open House Archive
Welcome to the Open House Archive - your central repository for accessing all previous Open House buildathons and projects.

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songsu
elpabl0.eth
contact ai
zorzalcripto
Rick
Amaan Sayyad
FounderSea is a decentralized idea funding & development platform built on Mantle
Bastion Protocol is an autonomous threat detection agent deployed on Robinhood Chain (Arbitrum Orbit L2, Chain ID 46630). It monitors the mempool in real time, scores every block using an 8-element feature vector, runs a 4-state FSM (NORMAL→ELEVATED→TRIPPED→COOLDOWN), and writes hash-committed detection proofs on-chain before exploits confirm. 5,880 scan cycles. 24/7 on Railway. 2 smart contracts deployed. 11 Alchemy components. 5 exploit patterns detected. Telegram alerts. Zero-cost gas-sponsored attestations. DeFi lost $1.8B to exploits in 2025. Flash loans, oracle manipulation, reentrancy, rug pulls, and MEV sandwiches execute in seconds. Existing tools alert after funds are gone. Bastion detects before the transaction lands.
Sellers publish AI agents. Buyers hire them in one wallet signature. USDC settles on Arbitrum the same block. Optional FHE-encrypted memory carries state between iterations.
Dynamic LP protection instead of guaranteed wipeouts!! A Partially Active AMM with zero-liquidation lending, powered by a high-performance Rust kernel on Arbitrum Stylus.
ROSA digitises rotating savings circles (Sou-Sous) on-chain using Arbitrum Stylus & ZeroDev Passkeys: features gasless onboarding, multi-chain support, and smart collateral default protection.
A compliant, institutional-grade lending protocol deployed on Robinhood Chain L2 using tokenized real-world equities as collateral.
A deterministic orchestrator that scans smart contracts, simulates attacks, proves every result cryptographically, and stores immutable audit reports on-chain via Stylus on Arbitrum. No LLM override.
NairaStable is a decentralized stablecoin pegged to the Nigerian Naira, built on Arbitrum. Users deposit ETH as collateral and mint nNGN. No bank, no custodian, just code.
Tacet is a sealed coordination protocol where autonomous agents commit privately, wait for a shared Drand cue, and settle deterministically on Arbitrum.
One continuous curve instead of a hundred yes/no pools — a Gaussian-priced prediction market, with all the math running on-chain via Arbitrum Stylus.
A verifiable-inference marketplace for the agent economy, on Arbitrum
Coffhee is an encrypted privacy-preserving DEX (eAMM).