SplitChain

The problem it solves

🌀 Fragmented Bill Splitting Experience Most existing bill-splitting tools (like Splitwise) are centralized, disconnected from payment platforms, and require manual tracking. There’s no seamless way to track, pay, or verify payments — users still need to pay via separate apps like Paytm, Venmo, or UPI.

⛓️ Lack of Onchain Transparency Current apps don’t offer onchain tracking. There's no transparent, immutable ledger showing who paid what, when, or how. This creates trust issues and confusion within friend groups.

⏳ Pay Later but Trust Issues "Pay Later" agreements often rely on personal trust, with no real system to ensure someone will pay. Friends become uncomfortable asking for repayments.

🧾 No Escrow or IOU Security Existing platforms lack secure, automated escrow mechanisms. There’s no way to lock funds in a smart contract and enforce repayment obligations onchain.

💬 No Social Accountability Social pressure and gamification can motivate people to pay promptly — but current platforms do nothing to encourage good behavior. There's no way to make repayments visible or “cool” in a social setting.

Challenges we ran into

🔗 Integrating WalletConnect with Frames/MiniKit One of the biggest technical challenges was integrating WalletConnect functionality smoothly within a Farcaster Frame and MiniKit context. Managing session persistence and ensuring secure connections across different environments (web, mobile) was non-trivial.

📜 Smart Contract Design for IOUs & Escrow Designing smart contracts that fairly represent IOUs and allow “Pay Later” logic required thoughtful architecture. Ensuring they were gas-efficient, secure, and allowed both parties to settle or dispute required iteration and testing.

🧠 UX for Onchain Interactions Translating complex blockchain actions like signing, escrowing, and splitting into a user-friendly UI inside Frames was tricky. Many users are new to web3, so creating a seamless flow without confusing the user was a key challenge.

🧪 Farcaster Frame Constraints Farcaster Frames have limited interactivity compared to full dApps. Balancing what could be done inside a Frame vs. redirecting to a full page for payment flow required trade-offs and creative decisions.

💸 Stablecoin Payment Flow Implementing Base USDC payments with proper fallback handling (e.g., insufficient balance, gas estimation) required real-time feedback to users and solid wallet integration logic.

🛡️ Security Considerations Handling user funds — even in escrow — demanded careful contract auditing, replay protection, and making sure users couldn’t spoof payment status or skip repayments.

⏱️ Time Management & Coordination Managing smart contract deployment, UI/UX design, wallet integrations, and social logic within a short timeframe (hackathon or sprint) meant rapid prototyping and prioritizing core features.