Open House Archive

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

All Projects

By Project By Buildathon

bond.credit

The credit layer for the agentic economy.

Tech StackPython, Solidity, Typescript

Builder

DeFiAI

Youtube Summarizer

Summarizes any youtube video by pasting the video URL

Tech StackJava, PHP

Builder

AI

FortiLayer

"Make Arbitrum the default execution layer for institutional capital by providing programmable, composable policy controls that enforce compliance on every on-chain transfer. FortiLayer turns Arbitrum

Tech StackSolidity, Rust, Web3, Ethers, React, Node

Builder

InfraDeFiDAORWA

Orinx

Orinx allows users to receive, hold, and send funds onchain while protecting their financial privacy.

Tech StackReact, Next, Vue, Web3, Ethers, Node, Solidity

Builder

DeFiInfraOther

RoboLend

Borrow WETH against tokenized equities on Robinhood Chain.

Tech StackSolidity, Next, React, Rust

Builder

DeFiRWA

Detective

Farcaster native game (mini app) where players wager ETH spotting AI clones. Built on Arbitrum with Solidity + Rust for on-chain reputation & Proof of Humanity.

Tech StackReact, Next, Rust, Web3, Ethers, Node

Builder

GamingAI

TXExplain

TXExplain is a transaction explainer project that generates a fully detailed explanation of a transaction on Arbitrum One using the transaction hash

Tech StackEthers, Web3

Builder

DeFiDAOAIOther

ZKperps

One-click for Private Perpetuals

Tech StackSolidity, React, Nextjs, circum

Builder

DeFi

Swiftrail

SwiftRail is a gasless USDC checkout stack for Arbitrum Sepolia. Customers sign once with USDC permit and do not pay ETH gas. A relayer sponsors gas, takes a small fee, and settles net USDC to the me

Tech StackRust, Web3, Ethers

Builder

DeFiOther

Agent Multiverse

The trust layer infrastructure for AI agents onchain identity, registry, and economic primitives for the open agentic web built on Arbitrum .

Tech StackNext, Solidity

Builder

InfraAIDeFi

ArbiLoop

ArbiLoop is an Arbitrum-native DeFi app for lending, borrowing, and loop strategies.It is non-custodial, automation-first, and focused on safer, more efficient DeFi management.

Tech StackNext, Node, Solidity, Javascript

Builder

DeFi

Stealthpay

Instead of turning the blockchain into a fully opaque privacy layer (which undermines the transparency that made blockchains valuable in the first place), we built StealthPay—an opt-in privacy primitive for users who don’t want their on-chain activity easily trackable, while still preserving the public verifiability of transactions. StealthPay is built on ERC-5564 (Stealth Addresses) and ERC-6538 (Stealth Meta-Address Registry), using the stealth “announcer” flow to enable users to send and receive funds on-chain via one-time stealth addresses rather than their public wallet address. For this hackathon, we shipped an MVP focused on core stealth transfers. Post-hackathon, we plan to expand with features like P2P flows, ENS-based routing (we hit an ENS resolver issue on Arbitrum during implementation, which we also want to support as a first-class feature), a message/inbox experience, and other privacy-forward UX improvements.

Tech StackReact, Node, Ethers, Web3, Solidity

Builder

OtherDeFi

Learn

Explore Course

Build

Hack

Hack Coming Soon

Builder Highlight

Most Buildathon Won

M

Manobendra Mandal

Kolkata, India

3

No.1

V

Vivek Sahu

India

2

No.2

s

simp1e

china

2

No.3

Most Project Built

M

Manjeet Sharma

india

16

No.1

R

Rick

California

16

No.2

D

DHRUV PANCHOLI

jaipur

15

No.3

Builder Highlight

Most Hackathon Won

Most Project Built

Builder Highlight

Most Buildathon Won

M

Manobendra Mandal

Kolkata, India

3

No.1

V

Vivek Sahu

India

2

No.2

s

simp1e

china

2

No.3

Most Project Built

M

Manjeet Sharma

india

16

No.1

R

Rick

California

16

No.2

D

DHRUV PANCHOLI

jaipur

15

No.3

Project Highlight

EduBricks

EduBricks is a platform enabling fractional ownership of tokenized real estate, making investments more accessible

7th Place

Arbitrum X EDU Chain Mini-Hack

Pencil Finance

Bringing $3 Trillion in Student Loans On-Chain

1st Place

Arbitrum X EDU Chain Mini-Hack

Stylish Course to Stylus Smart Contract Development

A comprehensive course on deploying and interacting with Stylus smart contracts on Arbitrum and EDU Chain, featuring a full-fledged Stylus IDE for seamless deployment and interaction.

First Prize

Arbitrum X EDU Chain Mini-Hack

VineFinance

Vine Finance is a decentralized, modular revenue strategy protocol.

Third Prize

Arbitrum X EDU Chain Mini-Hack

Orbital

A next-gen AMM that supports 2, 3, or even 10,000 stablecoins in a single pool, scaling concentrated liquidity into higher dimensions.

+1

Second prize

Arbitrum Open House India: Online Buildathon

zkArb SDK

zkArb SDK is a developer toolkit that makes building zero-knowledge apps on Arbitrum simple and fast. It provides plug-and-play Circom circuit compilation, proof generation, and ready-to-deploy verifier contracts, so developers can focus on dApps instead of cryptography.

Honorable Surprise Mention

Arbitrum Open House India: Online Buildathon

Project Highlight

EduBricks

EduBricks is a platform enabling fractional ownership of tokenized real estate, making investments more accessible

7th Place

Arbitrum X EDU Chain Mini-Hack

Pencil Finance

Bringing $3 Trillion in Student Loans On-Chain

1st Place

Arbitrum X EDU Chain Mini-Hack

Stylish Course to Stylus Smart Contract Development

A comprehensive course on deploying and interacting with Stylus smart contracts on Arbitrum and EDU Chain, featuring a full-fledged Stylus IDE for seamless deployment and interaction.

First Prize

Arbitrum X EDU Chain Mini-Hack

VineFinance

Vine Finance is a decentralized, modular revenue strategy protocol.

Third Prize

Arbitrum X EDU Chain Mini-Hack

Orbital

A next-gen AMM that supports 2, 3, or even 10,000 stablecoins in a single pool, scaling concentrated liquidity into higher dimensions.

+1

Second prize

Arbitrum Open House India: Online Buildathon

zkArb SDK

zkArb SDK is a developer toolkit that makes building zero-knowledge apps on Arbitrum simple and fast. It provides plug-and-play Circom circuit compilation, proof generation, and ready-to-deploy verifier contracts, so developers can focus on dApps instead of cryptography.

Honorable Surprise Mention

Arbitrum Open House India: Online Buildathon

bond.credit

The credit layer for the agentic economy.

Tech StackPython, Solidity, Typescript

Builder

DeFiAI

Youtube Summarizer

Summarizes any youtube video by pasting the video URL

Tech StackJava, PHP

Builder

AI

FortiLayer

"Make Arbitrum the default execution layer for institutional capital by providing programmable, composable policy controls that enforce compliance on every on-chain transfer. FortiLayer turns Arbitrum

Tech StackSolidity, Rust, Web3, Ethers, React, Node

Builder

InfraDeFiDAORWA

Orinx

Orinx allows users to receive, hold, and send funds onchain while protecting their financial privacy.

Tech StackReact, Next, Vue, Web3, Ethers, Node, Solidity

Builder

DeFiInfraOther

RoboLend

Borrow WETH against tokenized equities on Robinhood Chain.

Tech StackSolidity, Next, React, Rust

Builder

DeFiRWA

Detective

Farcaster native game (mini app) where players wager ETH spotting AI clones. Built on Arbitrum with Solidity + Rust for on-chain reputation & Proof of Humanity.

Tech StackReact, Next, Rust, Web3, Ethers, Node

Builder

GamingAI

TXExplain

TXExplain is a transaction explainer project that generates a fully detailed explanation of a transaction on Arbitrum One using the transaction hash

Tech StackEthers, Web3

Builder

DeFiDAOAIOther

ZKperps

One-click for Private Perpetuals

Tech StackSolidity, React, Nextjs, circum

Builder

DeFi

Swiftrail

SwiftRail is a gasless USDC checkout stack for Arbitrum Sepolia. Customers sign once with USDC permit and do not pay ETH gas. A relayer sponsors gas, takes a small fee, and settles net USDC to the me

Tech StackRust, Web3, Ethers

Builder

DeFiOther

Agent Multiverse

The trust layer infrastructure for AI agents onchain identity, registry, and economic primitives for the open agentic web built on Arbitrum .

Tech StackNext, Solidity

Builder

InfraAIDeFi

ArbiLoop

ArbiLoop is an Arbitrum-native DeFi app for lending, borrowing, and loop strategies.It is non-custodial, automation-first, and focused on safer, more efficient DeFi management.

Tech StackNext, Node, Solidity, Javascript

Builder

DeFi

Stealthpay

Instead of turning the blockchain into a fully opaque privacy layer (which undermines the transparency that made blockchains valuable in the first place), we built StealthPay—an opt-in privacy primitive for users who don’t want their on-chain activity easily trackable, while still preserving the public verifiability of transactions. StealthPay is built on ERC-5564 (Stealth Addresses) and ERC-6538 (Stealth Meta-Address Registry), using the stealth “announcer” flow to enable users to send and receive funds on-chain via one-time stealth addresses rather than their public wallet address. For this hackathon, we shipped an MVP focused on core stealth transfers. Post-hackathon, we plan to expand with features like P2P flows, ENS-based routing (we hit an ENS resolver issue on Arbitrum during implementation, which we also want to support as a first-class feature), a message/inbox experience, and other privacy-forward UX improvements.

Tech StackReact, Node, Ethers, Web3, Solidity

Builder

OtherDeFi