Overview
Setula helps UAE agencies pay overseas contractors in local currency, with USDC settling on Arc under the hood.
Live demo · GitHub repository · ArcScan proof
The problem
Cross-border contractor payments are fragile:
- The recipient cannot be certain what amount will arrive after FX and fees.
- Invoices and payment records live in separate systems.
- Payment stages are opaque — the sender does not know whether settlement completed, whether the payout reached the recipient, or where the failure occurred.
- Failures require manual investigation across payment partners, bank statements, and ledger entries.
The solution
Setula turns a cross-border contractor payment into a single tracked journey:
AED quote → AED funding → USDC settlement on Arc → INR payout → invoice-linked receipt
The finance user sees only the AED amount they approve and the INR amount the contractor receives. USDC settlement is handled by the payment partner infrastructure — Circle wallets transfer value on Arc Testnet, and Setula surfaces the Arc transaction as machine-verifiable proof.
Primary user
A finance manager at a small UAE agency paying an overseas contractor.
Hackathon scope
- One UAE agency
- One India-based contractor
- One invoice (INR 91,000)
- Sandbox AED-to-INR quote (fixed 22.75 INR/AED)
- Simulated AED funding
- Real USDC settlement on Arc Testnet (0.01 USDC)
- Simulated INR bank payout
- Invoice-linked payment tracking and receipt
- Duplicate and failure protection
Golden path
The happy-path journey follows seven payment states:
DRAFT → QUOTED → FUNDED → SETTLEMENT_PENDING → SETTLED → PAYOUT_PENDING → DELIVERED
- User enters contractor and invoice details.
- Setula generates a sandbox AED-to-INR quote.
- User approves the payment.
- AED funding is simulated.
- A real USDC transfer executes on Arc Testnet.
- INR payout is simulated.
- Setula shows the payment as delivered.
- User views the ArcScan transaction and receipt.
What is real and simulated
| Component | Status |
|---|---|
| Quote generation | SANDBOX (fixed 22.75 INR/AED rate) |
| AED collection | SIMULATED |
| Circle wallet settlement | REAL |
| USDC transfer on Arc Testnet | REAL |
| Arc transaction proof | REAL |
| INR bank payout | SIMULATED |
| Invoice and receipt reconciliation | REAL (application logic) |
AED funding and INR delivery are simulated demo flows. USDC settlement on Arc Testnet is a real on-chain transfer. The browser never receives Circle credentials or the payout callback secret.
Architecture diagram
Why Arc
- USDC settlement — a stable, widely-supported digital dollar.
- Deterministic transaction confirmation — the settlement outcome is unambiguous.
- Predictable USDC-denominated execution cost — no surprise fees during transfer.
- Machine-verifiable settlement evidence — every transfer produces a transaction hash retrievable on ArcScan.
- Reconciliation through transaction hashes — the hash uniquely links the payment record to the on-chain settlement.
Arc does not perform AED collection or INR delivery. Setula handles those legs through simulated funding and payout in this prototype.
Not in scope
The hackathon MVP intentionally excludes:
- Batch payments or multiple contractors
- Live AED collection or INR payout
- KYC / KYB or regulatory compliance
- CCTP, gateway, or paymaster features
- Admin dashboard or analytics